Generation of terahertz radiation with extreme parameters using a multipetawatt laser beam

Interaction of a laser pulse with a peak power of 15 PW with a solid film target in the reflection and transmission regimes is simulated numerically. The frequency-angular spectra of radiation in the terahertz (THz) range, as well as the parameters of accelerated electrons for these cases, are obtained. The dimensionless strength of the THz field is units of a₀, which upon focusing will make it possible to achieve relativistic intensities in the THz range.