| Abstract: | The multiple filamentation of terawatt femtosecond(fs) laser pulses is experimentally studied in a natural environment.A more than 30-m long plasma filament with a millimeter diameter is formed by the collimated fs laser pulse freely propagating in an open atmosphere. This study provides the first quantitative experimental data about the electron density of a long range light filament in the atmosphere. The electron density of such a filament is quantitatively detected by using an electric method, showing that it is at the 10~(11)-cm~(-3) level. |
