Interaction of an electromagnetic wave packet with an ionization front: copropagating configuration

The interaction of a TM polarized wave packet with a moving ionization front is theoretically investigated. We extend our previous study [IEEE Trans. Plasma Sci. 27, 655 (1999)], where we considered the case when the wave packet is incident on the front, by including the case often used in experiments when the front overtakes the wave packet. We focus on the energy transformation into the generated waves-the point that is rarely addressed in literature due to complications arising from the presence of Langmuir waves. Our quantitative results show the importance of losses via Langmuir wave excitation compared to other possible losses due to the excitation of stationary transverse electron currents in the plasma. Applicability to the generation of frequency upshifted radiation is discussed.