Calculation of Soft X-Ray Pulse Parameters on GAMMA-4 Facility

This paper presents the results of predictive calculations of the parameters of pulses of soft X-ray radiation (SXR) on a four-module electrophysical facility GAMMA-4 (the current pulse amplitude is ~3 MA with rise time of ~60 ns) that has been constructed in Russia. Scaling numerical simulation of implosion of a cylindrical single and nested multiwire array in 0-D, 2-D, and 3-D radiation magnetohydrodynamic- approximations is performed, taking into account, the updated double-loop equivalent electrical circuit of the GAMMA-4. The main purpose of the conducted studies was the numerical optimization of the multiwire array parameters to obtain the best characteristics of the SXR pulse generated as a result of Z-pinch implosion on the axis of the system.

I. Introduction

To obtain estimates of the output parameters of modern electrophysical pulsed power facilities that utilize dynamic loads of the Z-pinch type, various calculation methods are used, beginning with simplified 0-D models and ending with complex multidimensional radiation magnetohydrodynamic (RMHD) simulation. The existing set of verified computer codes can accurately reproduce the basic processes of the Z-pinch implosion. In this paper, we present the results of calculations of the parameters of the generated soft X-ray radiation (SXR) pulses, which are supposed to be obtained using a multiwire Z-pinch at GAMMA-4 facility. This facility is similar in its operating performance to Angara 5-1 facility [2] and takes a position between research pulsed power generators of 1-MA level located in Cornell (Cobra), Reno (Zebra), Michigan (LTD) Universities [3], and more powerful generators such as the Primary Test Stand (PTS) [4], Saturn [5], which are able to drive a dynamic load as Z-pinch by current pulse with amplitude of 7–9 MA and duration of less than 100 ns.