X-ray diagnostics for an MTF initial target plasma

Summary form only given. Theoretical and experimental investigations are in progress at the Los Alamos National Laboratory (LANL) in developing a suitable initial plasma for magnetized target fusion (MTF). Current investigation involves the production of a plasma using a z-directed current of 1-2 MA through either a gas fill or a 200 mm diameter frozen gas fiber along the axis. The resulting plasma is supported by a 2 cm radius by 2 cm high metallic wall. During the formation, the plasma is expected to have temperatures ranging from 50 eV to in excess of 500 eV, and densities in the neighborhood of 10/sup 18/cm/sup -3/. As a component of a diverse range of diagnostics fielded or to be fielded on the experiments, the X-ray emissions from the plasma are being characterized to provide temperature information about the plasma, using a multi-channel soft X-ray absorption/scattering spectrometer. The X-ray emissions are first passed through a set of filters and the resultant filtered X-rays are detected by an array of X-ray sensitive silicon diodes. The paper will present the conceptual design studies leading to the selection of the filters, and the analytical techniques for deconvoluting the X-ray data. The design studies involve the simulation of the diode response to X-ray emissions from hypothetical temperature and density profiles in the plasma, and also sensitivity studies on the capability of the spectrometer to resolve the emissions from possible impurities, Preliminary indications of the temperature obtained in plasmas formed in experiments using gas fill will also be presented.