Commissioning and power flow studies of the 2.5-MeV Ursa Minor LTD

Abstract

Ursa Minor is a 21-cavity Linear Transformer Driver (LTD) that has been built to evaluate LTD technology as a driver for electron beam diode research. Initial testing has been conducted at ±90 kV charge. In this configuration the generator has produced 2.0 MV on a 30-ohm MITL when driving an electron beam diode. 2-D PIC simulations of the MITL predict about 15% higher peak voltage and current than seen in experiments. Monte Carlo radiation transport calculations indicate the measured x-ray dose is consistent with the measured diode current and voltage. Triggering experiments indicate that single LTD cavities are insensitive to trigger polarity, whereas the 21-cavity Ursa Minor shows clear sensitivity to trigger polarity.

A Primer on Pulsed Power and Linear Transformer Drivers for High Energy Density Physics Applications

“…The early days of the BLUE pulsed-power facility at the University of Michigan. These four LTD cavities were previously part of the 21-cavity Ursa Minor facility at Sandia National Laboratories [18], [34], [131], [132]. issues to be investigated.…”

Design of a reversible polarity LTD for electron beam diode research

“…The accelerator design shown in Fig. 1 and the circuit models of the accelerator are based on the Ursa Minor accelerator [9], [10]. Circuit simulations were used to select the number of switches per cavity, capacitance, and number of cavities required to meet the design requirement.…”