One-dimensional moving bunches of charged particles in a plasma

The paper deals with the stability of one-dimensional moving bunches of charged particles in a plasma. It is shown that these bunches are unstable with the formation of a dense nucleus and a precursor stretched foward in the direction of the movement. A possibility of the existence of a stable bunch with the relatively low number of charged particles, a cluster, is discussed. Stability of such clusters is determined by scattering magnitude of their particles for velocities (or by the temperature). The clusters with temperature below critical are stable