arXiv subjects

Siba Prasad Acharya

Publications and source records attributed to Siba Prasad Acharya.

5 recordsLinked to original sources

arXiv2026

Linear and nonlinear characteristics of high frequency electrostatic drift waves in absence of collisions

High frequency electrostatic drift waves are shown as hybrid modes generated by mixing with cyclotron dynamics and grow at the expense of cyclotron modes due to mode coupling effects. The role of density gradient is to break the symmetry between the two cyclotron branches with strong values of the gradient causing the branch modified by drift to overlap with the cyclotron branch leading to a mode coupling instability. The analysis is carried out in the framework oof a fluid model without invoking collisional or finite Larmor radius effects. A second order nonlinear equation with variable coefficients has been derived to govern the dynamics of high frequency electrostatic drift waves in a moving frame of (2+1) spatio-temporal dimensions to show the wave characteristics in various parameter ranges. The possibilities of excitation of the high frequency electrostatic drift waves have been explored in the context of certain laboratory and astrophysical plasma systems including tokamaks and solar corona where the existence of steeper density gradients is more probable.

physics.plasm-ph↗

arXiv2023

Bending of pinned dust ion acoustic solitary waves in presence of charged space debris

We consider a low temperature plasma environment in the Low Earth Orbital (LEO) region in presence of charged space debris particles. The dynamics of (2+1) dimensional nonlinear dust ion acoustic waves with weak transverse perturbation, generated in the system is found to be governed by a forced Kadomtsev-Petviashvili (KP) equation, where the forcing term depends on charged space debris function. The bending phenomena of some exact dust ion acoustic solitary wave solutions in x-t and x-y planes are shown; that are resulted from consideration of different types of possible localized debris functions. A family of exact pinned accelerated solitary wave solutions has been obtained where the velocity changes over time but the amplitude remains constant. The shape of debris function also changes during its propagation. Also, a special exact solitary wave solution has been derived for the dust ion acoustic wave; that gets curved in spatial dimensions with the curvature depending upon nature of forcing debris function. Such intricate solitary wave solutions may be useful in modelling real experimental data.

physics.plasm-ph↗

arXiv2023

Accelerated magnetosonic lump wave solutions by orbiting charged space debris

The excitations of nonlinear magnetosonic lump waves induced by orbiting charged space debris objects in the Low Earth Orbital (LEO) plasma region are investigated in presence of the ambient magnetic field. These nonlinear waves are found to be governed by the forced Kadomtsev-Petviashvili (KP) type model equation, where the forcing term signifies the source current generated by different possible motions of charged space debris particles in the LEO plasma region. Different analytic lump wave solutions that are stable for both slow and fast magnetosonic waves in presence of charged space debris particles are found for the first time. The dynamics of exact pinned accelerated lump waves is explored in detail. Approximate lump wave solutions with time-dependent amplitudes and velocities are analyzed through perturbation methods for different types of localized space debris functions; yielding approximate pinned accelerated lump wave solutions. These new results may pave new direction in this field of research.

physics.plasm-ph↗

arXiv2023

Charged space debris induced nonlinear magnetosonic waves using inertial magnetohydrodynamics

The excitations of nonlinear magnetosonic waves in presence of charged space debris in the low Earth orbital plasma region is investigated taking into account effects of electron inertia in the framework of classical magnetohydrodynamics, which is also referred to as inertial magnetohydrodynamics. Magnetosonic waves are found to be governed by a forced Kadomtsev-Petviashvili equation with the forcing term representing effects of space debris particles. The dynamical behaviors of both slow and fast magnetosonic solitary waves is explored in detail. Exact accelerated magnetosonic lump solutions are shown to be stable for the entire region in parameter space of slow waves and a large region in parameter space of fast waves. In a similar way, magnetosonic curved solitary waves become stable for a small region in parameter space of fast waves. These exact solutions with special properties are derived for specific choices of debris functions. These novel results can have potential applications in scientific and technological aspects of space debris detection and mitigation.

physics.plasm-ph↗

arXiv2023

Nonlinear dynamical modelling of high frequency electrostatic drift waves using fluid theoretical approach in magnetized plasma

A novel third order nonlinear evolution equation governing the dynamics of high frequency electrostatic drift waves has been derived in the framework of a plasma fluid model in an inhomogeneous magnetized plasma. The linear dispersion relation arising out of the fluid equations has been studied for the conventional low frequency and high frequency electrostatic drift waves. This equation is then decomposed into two second order equations as the order of the equation becomes reduced after this kind of decomposition under certain conditions. The detailed analysis of fixed points as well as bifurcations of the phase portraits have been performed using the theory of planar dynamical systems. Then some exact as well as approximate travelling wave solutions of this reduced nonlinear equation for the high frequency electrostatic drift waves are derived. As the other second order reduced equation is linear in nature, its exact oscillatory and exponential solutions are derived. The intersection of the solutions of these two reduced second order equations provides the solutions of the original third order nonlinear evolution equation; it is verified that the solutions of the reduced nonlinear second order equation are subsets of the oscillatory solution of the reduced linear second order equation in most cases whereas the intersection is different if the exponential solution of the reduced linear second order equation is considered. So the solutions of the reduced second order nonlinear equation can directly represent the solutions of the original third order nonlinear equation representing the dynamics of the nonlinear high frequency electrostatic drift waves if the oscillatory solution of the reduced linear equation is considered.

physics.plasm-ph↗