Spectral Diagnostics Of An Optical Discharge Propagating Along A Hollow-Core Optical Fibre

The results of spectral diagnostics of an optical discharge (OD) plasma propagating through a hollow-core revolver fibre under the action of repetitively pulsed laser radiation are presented. The revolver fibre is made of silica glass, with a diameter of the hollow core being 20 pm. The peak values of the laser radiation intensity reach 10(12) W cm(-2) at an average Nd:YAG laser power of about 2 W. The time-averaged spectrum of the OD plasma in the visible range has the form of a continuum and is close to the blackbody spectrum with a temperature of 13.3-17 kK. The form of the spectrum dots not depend on the gas filling of the fibre core (air or argon). In the I 'V part of the spectrum, lines of neutral silicon are observed, which are indicative of the partial evaporation of the reflecting cladding of the fibre.