Measurements are reported of the target neutralization current, the targetcharge, and the tangential component of the magnetic field generated as aresult of laser-target interaction by pulses with the energy in the range of 45mJ to 92 mJ on target and the pulse duration from 39 fs to 1000 fs. Theexperiment was performed at the Eclipse facility in CELIA, Bordeaux. The aim ofthe experiment was to extend investigations performed for the thick (mm scale)targets to the case of thin (micrometer thickness) targets in a way that wouldallow for a straightforward comparison of the results. We found that thin foiltargets tend to generate 20 to 50 percent higher neutralization current and thetarget charge than the thick targets. The measurement of the tangentialcomponent of the magnetic field had shown that the initial spike is dominatedby the 1 ns pulse consistent with the 1 ns pulse of the neutralization current,but there are some differences between targets of different type on sub-nsscale, which is an effect going beyond a simple picture of the target acting asan antenna. The sub-ns structure appears to be reproducible to surprisingdegree. We found that there is in general a linear correlation between themaximum value of the magnetic field and the maximum neutralization current,which supports the target-antenna picture, except for pulses hundreds of fslong.
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