REFLECTION OF MODIFIED KORTEWEG-DE-VRIES SOLITONS IN A PLASMA HAVING NEGATIVE-IONS

The variable coefficient modified Korteweg-de Vries (mKdV) equations f or incident and reflected solitons are derived and solved to study the reflection of compressive and rarefactive ion acoustic solitons at th e critical density in an inhomogeneous negative ion plasma, The polari ty of the incident compressive and rarefactive solitons is not altered during the reflection process. Increasing the density gradient reinfo rces the reflection of both compressive and rarefactive mKdV solitons, whereas enhancement of the unperturbed plasma density weakens the ref lection.