Atomic mass dependent electrostatic diagnostics of colliding laser plasma plumes

作者：Yeates P^*; Fallon C; Kennedy E T; Costello J T

来源：Physics of Plasmas, 2013, 20(9): 093106.

DOI：10.1063/1.4821979

The behaviours of colliding laser plasma plumes (C-p) compared with single plasma plumes (S-p) are investigated for 14 different atomic mass targets. A Faraday cup, situated at the end of a drift tube (L = 0.99 m), is employed to record the time-of-flight (TOF) current traces for all elements and both plume configurations, for a fixed laser intensity of I-p = 4.2 x 10(10) Wcm(-2) (F = 0.25 kJ cm(-2)). The ratio of the peak current from the C-p relative to twice that from the S-p is designated as the peak current ratio while the ratio of the integrated charge yield from the C-p relative to twice that from the S-p is designated as the charge yield ratio. Variation of the position of the Faraday cup within the drift tube (L = 0.33, 0.55, and 0.99 m) in conjunction with a lower laser fluence (F = 0.14 kJ cm(-2)) facilitated direct comparison of the changing TOF traces from both plasma configurations for the five lightest elements studied (C, Al, Si, Ti, and Mn). The results are discussed in the frame of laser plasma hydrodynamic modelling to approximate the critical recombination distance L-CR. The dynamics of colliding laser plasma plumes and the atomic mass dependence trends observed are presented and discussed.

• 出版日期2013-9