Fielding of the on-axis diagnostic package at Z

We have developed a comprehensive diagnostic package for observing z-pinch radiation along the pinch axis on the Z accelerator. The instrumentation, f ielded on the axial package, are x-ray diagnostics requiring direct lines o f sight to the target. The diagnostics require vacuum access to the center of the accelerator. The environment is a hostile one, where we must deal wi th an intense, energetic photon flux (> 100 keV) debris (e. g., bullets or shrapnel), and mechanical shock in order for the diagnostics to survive. In addition, practical constraints require the package be refurbished and uti lized on a once a day shot schedule. In spite of this harsh environment, we have successfully fielded the diagnostic package with a high survivability of the data and the instruments. In this article, we describe the environm ent and issues related to the reentrant diagnostic package's implementation and maintenance. (C) 1999 American Institute of Physics. [S0034-6748(99)61 601- X].