Model of suspension limiters

A model of the response of a suspension to a short, intense laser pulse is described. In the model the particles act as initiators ofthe response, which develops in the liquid. Back propagation ofthe active region toward the laser is the dominate feature ofthe response; it can be used to simplify the description. Novel features ofthe model are the assertion of the existence of a liquid "plasma", i.e., a high density of free carriers in the liquid, and the development ofthe plasma in accordance with the Saha relation. The two aspects of the response are absorption by the liquid plasma and scattering from gas bubbles. The relative role ofthese mechanisms depends on the particulars ofthe suspension and the intensity ofthe laser pulse. A computer code implementing the model is described and the results of simulations are presented. Limiting data and images of irradiated suspensions are compared with the predictions of the model. The images are of emitted and scattered light, as well as shadowgraphs. The implications ofthe model for the design of suspension limiters is discussed.