S K Mattoo
Articles written in Pramana – Journal of Physics
Volume 15 Issue 2 August 1980 pp 117-136 Plasma Physics
The paper emphasises the importance of plasma-neutral boundary layer in a wide variety of physical phenomena occurring in laboratory and cosmic plasmas. The interaction of a magnetised plasma stream penetrating a neutral gas cloud is discussed in the light of Alfvén’s critical velocity and Varma’s threshold velocity on the ionising interaction.
Interaction of a moving magnetised plasma with a stationary neutral gas has been studied and described. The device comprises of a plasma gun and an interaction region where neutral gas cloud is injected. The interaction region is provided with a transverse magnetic field of upto 1000 G. Several diagnostics deployed at the interaction region to make measurements on the macroscopic parameters of plasma and neutral gas are described. The parameters of discharge circuits are measured with high current and voltage probes.
An interaction between a magnetised plasma stream and a neutral gas cloud is demonstrated. It is shown that this interaction does not have Varma’s threshold on their relative velocity. The Alfvén’s critical velocity phenomenon is shown to depend on the integrated column neutral gas density that a plasma stream encounters while penetrating through it and not on the neutral gas density in the range of 1017–1021 m−2.
Volume 15 Issue 6 December 1980 pp 525-530 Plasma Physics
The double layer like potential jumps have been observed in a double plasma device. They do not correspond to a switching of plasma potential from one metastable state to another but are caused by the ionisation of a very minute amount of the gas that inevitably leaks into the system during the probe movement.
Volume 27 Issue 6 December 1986 pp 803-811 Plasma Physics
The paper describes a new scheme for suppressing the unwanted and dominant coupling of the diamagnetic coil with the toroidal field coils of a tokamak device.
Volume 55 Issue 5-6 November 2000 pp 727-732 Takamak Plasmas, Contributed Papers
The spatial and temporal structures of magnetic signal in the tokamak ADITYA is analysed using recently developed singular value decomposition (SVD) technique. The analysis technique is first tested with simulated data and then applied to the ADITYA Mirnov coil data to determine the structure of current peturbation as the discharge progresses. It is observed that during the current rise phase, current perturbation undergoes transition from