Finite amplitude solitary structures of coupled kinetic Alfven-acoustic waves in dense plasmas

Abstract

In this paper, we have investigated the nonlinear propagating coupled Kinetic Alfven-acoustic waves in a low beta degenerate quantum plasma in the presence of trapped Fermi electrons using the quantum hydrodynamic (QHD) model. By using the two potential theory and the Sagdeev potential approach, we have investigated the formation of solitary structures for coupled kinetic Alfven-acoustic waves in the presence of quantum mechanically trapped electrons. We have shown that there are regions of propagation and non-propagation for such solitary structures. We have also highlighted the differences between the classical and quantum mechanically trapped electrons. Interestingly, it has been found that the nature of the nonlinearity for the quantum mechanically trapped electrons is different from its classical counterpart. The results presented here may have applications in white dwarf asteroseismology as well as next generation laserplasma experiments where low beta plasma condition is met.

Effect of trapping in coupled kinetic Alfven-acoustic waves in a partially degenerate plasma with quantizing magnetic field

“…If we put the normalized temperature and quantizing magnetic field to be equal to zero, we retrieve the linear dispersion for a fully degenerate plasma, in accordance with Sabeen et al [18]. Unlike the classical cases, the effect of trapping remains visible as a 3/2 coefficient in the linear dispersion relation as well.…”

“…The value of constant C is given in equation (18). The second term in Hamiltonian shows effective potential [32] which in our case is the Sagdeev potential given in equation ( 17).…”

“…expression to get an exact solution for the system, losing the fractional non-linearity in the process, to a trapping co-efficient (as in 3 2 j) [17]. In certain cases [11][12][13][14]18], ( )…”

“…This work was later extended to a relativistic degenerate plasma [12] in the presence of a quantizing magnetic field [13]. Effect of trapping is also investigated for self-gravitating dusty plasma [14], and for kinetic Alfven waves (KAWs) in the classical case [19] and later for a fully degenerate plasma [18]. Recently, adiabatic trapping was investigated in a dissipative medium for ion acoustic waves in a magnetized plasma, where Burgers equation was derived, and nonlinear shock wave formation of different kinds was observed [20].…”

“…Lately, much promising work is still ongoing for the propagation of KAWs in non-Maxwellian kappa distributed electrons in space and upper atmospheric plasma [26,27], but not much is done for the aforementioned waves in quantum plasmas or dense astrophysical plasmas. This concept was extended by Sabeen et al [18] to quantum plasmas, where solitary structures were investigated for CKAAWs in a fully degenerate plasma.…”