Study of Heating Effects During Thomson Scattering in Laser Induced Plasma in Air

The laser induced plasma in air produced by 6 ns, 532 nm Nd:YAG pulses with 25 mJ energy was studied using the Thomson scattering method and plasma imaging techniques. Thomson scattering spectra were registered at delay times ranging from 150 ns to 1 mu s after the breakdown pulses. The electron density and temperature, as determined in the core of the plasma plume, were found to decrease from 7.4x10(17) cm(-3) to 1.0x10(17) cm(-3) and from 101 000 K to 22 700 K, respectively. These electron temperatures were found to result partially from plasma heating. This effect has been observed between the beginning and the end of the probe (Thomson) pulse. (c) 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim