Laha, S, Chen YC, Gupta P, Simien CE, Martinez YN, Mickelson PG, Nagel SB, Killian TC.
2006.
Kinetic energy oscillations in annular regions of ultracold neutral plasmas, Oct. European Physical Journal D. 40:51-56., Number 1
AbstractA study of ion equilibration in annular regions of ultracold strontium plasmas is reported. Plasmas are formed by photoionizing laser-cooled atoms with a pulsed dye laser. The experimental probe is spatially-resolved absorption spectroscopy using the S-2(1/2)-P-2(1/2) transition of the Sr+ ion. The kinetic energy of the ions is calculated from the Doppler broadening of the spectrum, and it displays clear oscillations during the first microsecond after plasma formation. The oscillations, which are a characteristic of strong coulomb coupling, are fit with a simple phenomenological model incorporating damping and density variation in the plasma.
] 