The MaPLE device of Saha Institute of Nuclear Physics: Construction and its plasma aspects

Abstract

The Magnetized Plasma Linear Experimental (MaPLE) device is a low cost laboratory plasma device at Saha Institute of Nuclear Physics fabricated in-house with the primary aim of studying basic plasma physics phenomena such as plasma instabilities, wave propagation, and their nonlinear behavior in magnetized plasma regime in a controlled manner. The machine is specially designed to be a versatile laboratory device that can provide a number of magnetic and electric scenario to facilitate such studies. A total of 36 number of 20-turn magnet coils, designed such as to allow easy handling, is capable of producing a uniform, dc magnetic field of about 0.35 T inside the plasma chamber of diameter 0.30 m. Support structure of the coils is planned in an innovative way facilitating straightforward fabrication and easy positioning of the coils. Further special feature lies in the arrangement of the spacers between the coils that can be maneuvered rather easily to create different magnetic configurations. Various methods of plasma production can be suitably utilized according to the experimental needs at either end of the vacuum vessel. In the present paper, characteristics of a steady state plasma generated by electron cyclotron resonance method using 2.45 GHz microwave power are presented. Scans using simple probe drives revealed that a uniform and long plasma column having electron density approximately 3-5x10(10) cm(-3) and temperature approximately 7-10 eV, is formed in the center of the plasma chamber which is suitable for wave launching experiments.

Investigation of long-range temporal correlation in electron cyclotron resonance produced linear magnetized plasma of the MaPLE device

“…The present experimental observations have been carried out in the MaPLE device 19 (schematic shown in Figure 1), which is a linear magnetized plasma device with an inner diameter of 30 cm and length of 240 cm. The base pressure in the device is 2 Â 10 À6 mbar and the operating pressure was kept in the region of 5 Â 10 À5 to 5 Â 10 À4 mbar with nitrogen as the working gas.…”

“…5 Electron cyclotron resonance (ECR) plasmas 10,11 are intensely ionized high density plasmas and hence very useful in various applications like plasma processing, 12,13 plasma thrusters, 14 preionization of Tokamak plasmas, [15][16][17][18] etc. In this article, the long range temporal correlation characteristics of low frequency floating potential fluctuations are investigated in the Magnetized Plasma Linear Experimental (MaPLE) device, 19 where plasma is produced by ECR. The values H estimated from R/S statistics are also compared with those calculated from power spectrum analysis.…”

The MaPLE device: A linear machine for laboratory studies of the magnetized plasma physics phenomena

“…The MaPLE device (Pal R. et al 2010;Biswas et al 2011;Biswas 2013;Pal A. M. et al 2014) is a linear machine with a cylindrical vacuum vessel where an axial, dc magnetic field is produced and the field is uniform over the radius and a length of 1.5 m inside the vacuum vessel. Schematic diagram of the device is shown in Fig.…”

“…Details of the magnetic field configuration and magnetic coil system is given in Ref. Pal R. et al (2010).…”

“…However, in spite of the wide variation of various parameters and scales among the astrophysical, fusion and others laboratories plasmas, physics of the waves and instabilities occurring in all these plasmas remains same. Keeping this fact in mind, a linear steady state plasma device, the MaPLE device (Pal R. et al 2010;Biswas 2013), has been designed and fabricated in house at the Saha Institute of Nuclear Physics with the specific intention of studying these waves in a controlled manner.…”