Title :
Photo-ionized lithium source for plasma accelerator applications
Author :
Muggli, P. ; Marsh, K.A. ; Wang, S. ; Clayton, C.E. ; Lee, S. ; Katsouleas, T.C. ; Joshi, C.
Author_Institution :
Dept. of Electr. Eng., Univ. of Southern California, Los Angeles, CA, USA
fDate :
6/1/1999 12:00:00 AM
Abstract :
A photo-ionized lithium source is developed for plasma acceleration applications. A homogeneous column of lithium neutral vapor with a density of 2×1015-3 is confined by helium gas in a heat-pipe oven. A UV laser pulse ionizes the vapor. In this device, the length of the neutral vapor and plasma column is 25 cm. The plasma density was measured by laser interferometry in the visible on the lithium neutrals and by CO2 laser interferometry on the plasma electrons. The maximum measured plasma density was 2.9×10 14 cm-3, limited by the available UV fluence (≈83 mJ/cm2), corresponding to a 15% ionization fraction. After ionization, the plasma density decreases by a factor of two in about 12 μs. These results show that such a plasma source is scaleable to lengths of the order of 1 m and should satisfy all the requirements for demonstrating the acceleration of electrons by 1 GeV in a 1-GeV/m amplitude plasma wake
Keywords :
collective accelerators; ion sources; lithium; photoionisation; CO2; CO2 laser interferometry; Li; Li neutral vapor; UV fluence; UV laser pulse; acceleration; density; heat-pipe oven; homogeneous column; ionization; ionization fraction; lithium neutrals; neutral vapor; photo-ionized lithium source; plasma acceleration; plasma accelerator applications; plasma column; plasma density; plasma electrons; plasma source; plasma wake amplitude; Density measurement; Gas lasers; Interferometry; Lithium; Plasma accelerators; Plasma confinement; Plasma density; Plasma devices; Plasma measurements; Plasma sources;
Journal_Title :
Plasma Science, IEEE Transactions on
