Visible self-emission and laser imaging diagnostics for the Z Machine.

Abstract

We present an overview of visible self-emission and laser imaging diagnostics for the Z Machine at Sandia National Laboratories. First, we review the Self-Emission Gated Optical Imager (SEGOI) diagnostic. SEGOI utilizes the Z Line Velocity Interferometer System for Any Reflector (Z Line VISAR) imaging relay system and detectors with a modified in-chamber optical configuration that is more flexible and significantly lower in cost. Detectors include eight intensified CCD (ICCD) cameras (540-600 nm) and two streak cameras (532 nm). The choice of in-chamber lens is flexible and determines the field-of-view (6.8-14 mm) and spatial resolution (∼32-74 μm edge widths). Next, we review the Laser Imaging on Z (LIONZ) diagnostic. LIONZ injects an open-beam 532 nm laser into the Z chamber via the Z Line VISAR beam transport system. This beam is redirected to the back of the target and then collected utilizing SEGOI. An additional 4-frame ICCD camera collects laser shadowgraphs, and one or both of the SEGOI streak cameras may be configured for streaked shadowgraphy, while the eight ICCD cameras for SEGOI may be simultaneously fielded for self-emission imaging. Currently, two open beam lasers with adjustable trigger times and a full-width-half-maximum of 20 ns are injected. Together, SEGOI and LIONZ offer valuable insight into the dynamics of low density plasmas on Z.