UV lasing in nitrogen pumped by a runaway electron preionised diffuse discharge

UV lasing is studied in nitrogen and the N-2-SF6 mixture pumped by a volume discharge initiated by a runaway-electron preionised diffuse discharge (REP DD) produced in an inhomogeneous electric field. It is shown, that lasing at a wavelength of 337.1 nm is observed at pressures up to 2.5 atm without any preionisation source. At a pressure of 0.5 atm with the use of blade electrodes and the N-2:SF6 = 10: 1 active medium of length similar to 6 cm, the output laser energy of similar to 2 mJ was achieved for the pulse power of 0.55 MW. The REP DD pumping regime is compared with the regime of pumping by a volume discharge produced by a preionisation source.