Back-bombardment effect is studied by the example of the 10MeV standing wave technological electron linac. The beam dynamics are calculated, the spectra of backstreaming electrons are obtained, the power released by the backstreaming electrons at the cathode was estimated. The observed effects are in good agreement with the calculations.
$^1$Skobeltsyn Institute of Nuclear Physics, Moscow State University,
$^2$Laboratory of Electron Accelerators MSU Ltd