Abstract:
Studies of the dependence of the radiation scattered by laser plasma directivity on the power density of laser radiation with a wavelength of 1.315 $\mu$m on the target, on the size and shape of the focal spot were carried out at the “Iskra-5”. It is shown that at a power density from 2 $\cdot$ 10$^{13}$ to 2 $\cdot$ 10$^{14}$ W/cm$^2$, the integral (in 4$\pi$) scattering loss is $\sim$ 50% of the pumping energy for various focal spot shapes and sizes ranging from 0.2 to 14 mm. In this case, the nature of the radiation diagram significantly depends on the intensity of the radiation, the shape and size of the focal spot and the directivity of the polarization vector.