We show that their time of initiation, their velocity and the distance they travel are directly dependent on the value of the applied voltage. We also show that these bullets can be controlled by the application of an external electric field. Using an intensified charge coupled device camera we report on their geometrical shape, which was revealed to be 'donut' shaped, therefore giving an indication that solitary surface ionization waves may be responsible for the creation of these bullets.
In addition, using emission spectroscopy, we follow the evolution of various species along the trajectory of the bullets, in this way correlating the bullet propagation with the evolution of their chemical activity.
Ref.: Experimental investigations of plasma bullets. 2009. N. Mericam-Bourdet et al. J. Phys. D: Appl. Phys. 42 055207 (7pp)
