Nitrogen capillary plasma as a source of intense monochromatic radiation at 2.88Â nm

Capillary discharge plasma related to our laboratory device is modeled and the results are compared with experimental data. Time dependences of selected plasma quantities (e.g. plasma mass density, electron temperature and density and emission intensities) evaluated by 2D Radiation-Magneto-Hydro-Dynamic code Z* describe plasma evolution. The highest output pulse energy at 2.88 nm wavelength is achieved for nitrogen filling pressure ∼100 Pa. The estimated output energy of monochromatic radiation 5.5 mJ sr−1 (∼1014 photons sr−1) corresponds properly to observe experimental value ∼3 × 1013 photons sr−1. Ray tracing inspection along the capillary axis proves an influence of radiation self-absorption for the investigated wavelength. The spectra, evaluated using the FLY code, agree to the measured ones.