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arXiv · 1201.4966

Velocity distribution of neutral particles ejected from biological material under ultra short laser radiation

Wolfgang Husinsky·Hatem Dachraoui
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Abstract

Neutral particles ejected from biological material under ultra short laser ablation have been investigated by laser post-ionization time-of-flight mass spectrometry. It could be shown, that beside ionized species, a substantial amount of neutral particles is ejected. A temporal study of the ablation plume is carried out by recording neutral particle time-of- flight mass spectra as a function of delay time between the ablation and post-ionization pulse. Close the ablation threshold, the mechanism of ejection is found to be of predominantely mechanical nature, driven by the relaxation of the laser-induced pressure. In this regime of stress confinement, the ejection results in very broad velocity distributions and extremely low velocities.

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Wolfgang Husinsky, Hatem Dachraoui. 2012-01-24. Velocity distribution of neutral particles ejected from biological material under ultra short laser radiation. https://arxiv.org/abs/1201.4966

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