Observation of suprathermal electrons produced by stimulated Raman scattering processes

Fast electrons (with E≫Te ) have been observed as pulses correlated in time with stimulated Raman backscatter pulses during CO2 laser interaction with cold underdense plasmas. Time-integrated electron spectra have a Maxwellian energy distribution, with discharge to discharge temperatures of 29–105 keV. Because the density is less than quarter critical and suprathermal electrons are seen only during discharges when stimulated Raman scattering occurs, it is concluded that Raman processes create the hot electrons.