Characterization of dust and debris collected from the Nova facility

Dust and debris were collected from the Nova laser facility in April 1999 t o provide evidence of particulate generation and transport mechanisms relev ant to fusion power safety analyses. Samples were obtained at specified loc ations within the Nova chamber with a vacuum filter system, cascade impacto rs, and metallurgical replicating tape (acetate tape). Average surface mass density of material collected from locations with measured surface area ra nges from 3.13 mug/cm(2) on the mid-plane vertical surface to 3250 mug/cm(2 ) on the vessel bottom. Estimated total dust inventory is 44 grams. Specifi c surface area of dust collected from several locations is nearly uniform w ith an average value of 0.435 m(2)/g. Particle size distributions of the co llected material show a range of count median diameters (CMD) between 0.67 and 1.19 mum with geometric standard deviations (GSD) between 1.63 and 2.76 . Mass median diameters for dust collected with the two cascade impactors a re 5.26 mum and 8.85 mum. The shape of the volumetric size distribution ind icates dust particles of various shapes. Composition analysis performed by energy dispersive X-ray analysis indicated the presence of O, Al, Cu, along with trace quantities of Fe, Au, and Be. Atomic emission ICP analysis also indicated the presence of Si, O, and Cu in dust samples.