The present experiment for the first time compares in detail angular emission characteristics of laser produced plasma pulses ablated from binary material of variable stoichiometry with each other and with those of its pure components. As an example system we have chosen Tungsten-Copper alloys (WCu). The plasma was produced by obliquely incident Q-switched laser pulses (E_(L) velence 125 mJ, tau velence 5 ns and lambda velence 1.06 (mu)m) focused to an ablation area of 1 mm~(2). The most remarkable results are: 1. The widths of the emission cones of neutrals and all ions systematically steepens as a function of the (average) atomic mass of the target. 2. The width is decreasing with increasing charge state. 3. The direction of the emission turns towards the direction of the incoming laser beam as a function of the particles charge state.
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