Laser absorption measurements of electron density in nanosecond-scale atmospheric pressure pulsed plasmas
T Yong, AI Abdalla, MA Cappelli - Physics of Plasmas, 2021 - pubs.aip.org
We report on time-resolved measurements of electron number density by continuous-wave
laser absorption in a low-energy nanosecond-scale laser-produced spark in atmospheric
pressure air. Laser absorption is a result of free-free and bound-free electron excitation, with
the absorption coefficient modeled and evaluated using estimates of the time-variation in
electron temperature and probe laser absorption path length. Plasma electron number
densities are determined to be as high as ne= 7× 10 19 cm− 3 and decay to 1/e of their peak …
laser absorption in a low-energy nanosecond-scale laser-produced spark in atmospheric
pressure air. Laser absorption is a result of free-free and bound-free electron excitation, with
the absorption coefficient modeled and evaluated using estimates of the time-variation in
electron temperature and probe laser absorption path length. Plasma electron number
densities are determined to be as high as ne= 7× 10 19 cm− 3 and decay to 1/e of their peak …