Papers by Alexandre Escarguel
European Journal of Physics, 2012
ABSTRACT In the framework of scientific outreach at the Maison des Sciences of Aix-Marseilles Uni... more ABSTRACT In the framework of scientific outreach at the Maison des Sciences of Aix-Marseilles University, we created a teaching kit for holography that can be packed into a small case. It includes all the equipment required to produce holograms almost anywhere and has a simple optical assembly and very good vibration tolerance. The fundamental principles of holography and several applications are illustrated through simple experiments: reflection Denisyuk holograms, angular multiplexing, notch filters, holographic interferometry and diffraction holographic gratings. It is possible to use this tool for several purposes: science outreach, teaching for undergraduate and graduate students and continuing education. In this paper, we explain the basis of holography, how the kit works and indicate some applications and results that can be performed and obtained with it.
Journal of Physics: Conference Series, 2013
ABSTRACT in the framework of scientific outreach at the "Maison des Sciences" o... more ABSTRACT in the framework of scientific outreach at the "Maison des Sciences" of the Aix-Marseilles University, we created a teaching kit for holography contained in a small case. It includes all the required equipment to produce holograms almost anywhere with a simple optical assembly with a very good vibration tolerance. The fundamental principles of holography and several applications are illustrated through simple experiments: reflection Denisyuk holograms, angular multiplexing, notch filters, holographic interferometry and diffraction holographic gratings. It is possible to use this tool for several purposes: science outreach, teaching for undergraduate and graduate students and continuing education. In this article, we explain the basis of holography, how the kit works, and give some applications and results that can be done with it.
Journal of Plasma Physics, 2016
The 14th international conference on spectral line shapes, 1999
Journal of Quantitative Spectroscopy and Radiative Transfer, 2000
A dense and relatively cold plasma is obtained, by a single laser breakdown in underwater medium.... more A dense and relatively cold plasma is obtained, by a single laser breakdown in underwater medium. For the "rst time, the Balmer H ? line is observed in such conditions. The spectrum is studied with a spatial and time resolved spectroscopic method. Traces of Ca and K are added to the water sample for the temperature and electron density measurements. Values of N as high as 6.2;10 cm and temperature lower than 10 K are reached simultaneously. Temperature and electron density are varied over a large range by varying the laser energy. The stability and the radial homogeneity of the plasma are studied. Abel inversion is used to estimate these radial inhomogeneity. Observed line pro"les are unfolded by a new method. The theoretical H ? widths, deduced from N and ¹ measured with K and Ca traces, are compared with the experimental Balmer H ? line widths. When the electron density grows, increasing discrepancies between them are observed. They are related to non-ideal plasma behaviour due to density correlation e!ects. (A. Escarguel) 0022-4073/99/$ -see front matter 1999 Elsevier Science Ltd. All rights reserved. PII: S 0 0 2 2 -4 0 7 3 ( 9 9 ) 0 0 1 0 8 -9
The turbulent regime of the rotating magnetized plasma column in the Mistral device has been stud... more The turbulent regime of the rotating magnetized plasma column in the Mistral device has been studied. The structures inside the turbulence move on average along a spiral trajectory. These long-lived structures are convected in the background plasma to the walls contributing to a large extent both to particle and to energy transport. Without drift induced by the curvature and the
The transition to turbulence of strongly nonlinear low frequency unstable waves obtained in a new... more The transition to turbulence of strongly nonlinear low frequency unstable waves obtained in a new magnetized plasma device is studied. The device consists in a large multipolar plasma chamber (1.4m diameter, 1 m length) connected to a cylinder (40 cm diam., 1m length) and a half-torus (40 cm diam., 0.61 m large radius). The linear and curved columns are surrounded
In a new divertor simulator, an ultra-cold (Te<1 eV) high density recombining magnetized labor... more In a new divertor simulator, an ultra-cold (Te<1 eV) high density recombining magnetized laboratory plasma is studied using probes, spectroscopic measurements, and ultra-fast imaging of spontaneous emission. The Mistral-B device consists in a linear high density magnetized plasma column. The ionizing electrons originate from a large cathode array located in the fringing field of the solenoid. The ionizing electrons are
A cylindrical column of magnetized plasma is produced by means of the hot cathode laboratory devi... more A cylindrical column of magnetized plasma is produced by means of the hot cathode laboratory device MISTRAL using various gases (Neon, Argon, Krypton). In usual experimental conditions, strongly nonlinear low frequency instabilities in the ion cyclotron range are recorded. A transition towards ion cyclotron turbulence appears to be triggered by a threshold value of the radial electric field. In order to investigate the characteristics of the instabilities and the phenomena responsible for the destabilization of the plasma column, detailed measurements are performed using various diagnostics (probe arrays, ultra-fast and intensified cameras, Laser Induced Fluorescence, spectroscopy, microwave resonance). The results are compared with both a theoretical model of the ion cyclotron instability and Particle in Cell simulation of the instability.
Arxiv preprint physics/ …, 2004
In a new divertor simulator, an ultra-cold (T e <1 eV) high density recombining magnetized labora... more In a new divertor simulator, an ultra-cold (T e <1 eV) high density recombining magnetized laboratory plasma is studied using probes, spectroscopic measurements, and ultra-fast imaging of spontaneous emission. The Mistral-B device consists in a linear high density magnetized plasma column. The ionizing electrons originate from a large cathode array located in the fringing field of the solenoid. The ionizing electrons are focused in a 3 cm diameter hole at the entrance of the solenoid. The typical plasma density on the axis is close to 2.10 18 m -3 . The collector is segmented into two plates and a transverse electric field is applied through a potential difference between the plates. The Lorentz force induces the ejection of a very-low temperature plasma jet in the limiter shadow. The characteristic convection time and decay lengths have been obtained with an ultra-fast camera. The study of the atomic physics of the recombining plasma allows to understand the measured decay time and to explain the emission spectra.
In the framework of scientific outreach at the Maison des Sciences of Aix-Marseilles University, ... more In the framework of scientific outreach at the Maison des Sciences of Aix-Marseilles University, we created a teaching kit for holography that can be packed into a small case. It includes all the equipment required to produce holograms almost anywhere and has a simple optical assembly and very good vibration tolerance. The fundamental principles of holography and several applications are illustrated through simple experiments: reflection Denisyuk holograms, angular multiplexing, notch filters, holographic interferometry and diffraction holographic gratings. It is possible to use this tool for several purposes: science outreach, teaching for undergraduate and graduate students and continuing education. In this paper, we explain the basis of holography, how the kit works and indicate some applications and results that can be performed and obtained with it. (Some figures may appear in colour only in the online journal)
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Papers by Alexandre Escarguel