Ponderomotive force acceleration

A completely different emission process, which can in principle provide table-top ultrashort X-ray sources up to 100 keV has been recently discovered and studied, both from an experimental and a theoretical viewpoint [9]. It can be understood as one consider that the electrons, trapped and accelerated in a plasma wake as described earlier, can also experience, in some cases, a transverse force pulling them toward the beam axis. This force is basically due to the creation of a sort of plasma channel at low electron density, which is a consequence of the ponderomotive force that expels the electrons from the laser beam axis (the ions, due to their larger inertia, being fixed). The trapped electrons thus undergo a sort of wiggler motion, thus producing so-called betatron radiation. 

Picosecond pedestal, 143 Pin-hole camera, 128 Plasma channels, 112, 147, 148 Plasma defocusing, 84, 91 Plasma frequency, 166 Plasma index of refraction, 147 Plasma mirror (PM) technique, 194 Plasma wakefield acceleration, 172 Plasma wavelength, 166 Plasma-induced effects, 83 Polarization, 97 Polarization control, 87 Ponderomotive force, 170 Population inversions, 19 Post-irradiation spectroscopy, 156 Pre-pulse, 143 Propagation, 81 Protein, 102 Pump depletion, 151... 

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