Control of radiative recombination by a strong laser field

Strong-field laser-assisted radiation recombination is investigated: (a) to explore the control possibilities with two laser fields having commensurable frequencies and (b) to get some insight into the influence of the medium (a plasma) in which recombination occurs. It is found that by varying the relative phase of the two fields it is possible to control enhancement, broadening and symmetry properties of the recombination differential emitted power. In the case of an anisotropic two-temperature plasma, an interesting interplay is found between the shape of the laser-modified electron velocity distribution function and the shape of the emitted X-ray photon power spectrum. The novel features of strong laser-assisted radiative recombination are mostly restricted to the region of the process parameters corresponding to the physical situation when the characteristic electron velocities (translation, quiver and thermal) are comparable. A classical picture allows a fairly good understanding of the process. PACS 32.80.Wr; 34.80.Lx; 34.50.Rk