X-ray-line plasma satellites of ions in solid target plasmas produced by picosecond laser pulse

The X-ray lines of ions in a solid target interacting with picosecond laser pulses of moderate intensity ($2\times 10^{17}$ W/cm$^2$) were measured on the «Neodim» laser facility. X-ray $Ly_\alpha$ emission spectra of hydrogen-like fluorine ions were observed. Satellite lines were also observed, evidencing the presence of intense plasma oscillations. The positions and separation between the satellites allow their assignment to the intense electrostatic oscillations with an amplitude larger than $10^8$ V/cm and a frequency of about $7\times 10^{14}$s$^{-1}$ that is noticeably lower than the laser frequency $\omega_{\mathrm{las}}\sim 1.8\times 10^{15}$s$^{-1}$. It is suggested that these oscillations may be due to strong plasma turbulence caused by the development of plasma oscillations of the Bernstein-mode type under the action of a strong magnetic field generated in plasma. The experimental results are compared with the calculated spectra of multicharged ions.