Deep UV spectroscopic, X-ray diagnostics and high performance computational tools for designing ultr
Abstract
Tube based crossed field devices such as the magnetron or the MILO are capable of producing short bursts of electromagnetic energy which under the right conditions can render electronics inoperable or unstable[1,2]. It is critical to put even more energy onto electronic targets if this effect is to increase from temporary to longer term or even permanent. Although crossed field devices may be at the threshold of novel advancements – frequency agility recently shown by this group with gigawatt pulses, they are not capable of producing long pulses and also struggle to have anything but low repetition rates[3,4,5]. This is the critical limiting factor for HPM sources and has severely limited the effectiveness of HPM devices for weapons applications. The root of the problem lies in the electron beam neutralization that results from ions moving through the interaction space. The ions themselves are born via electron impact liberating neutrals on the cathode and anode surface followed by ionization of these neutrals[6,7]. The solution is to mitigate the impact of these time and space evolving plasmas occurring in the interaction space[7,8]. The key path for mitigating the effects of these plasmas and produce a viable field deployable HPM weapon is to have a dual pronged approach coupling state of the art computational simulations with carefully developed experiments that measure the evolving plasmas not just in space but also in time. This calls for time resolved and spatially resolved diagnostics that measure the evolution of these plasmas, their density, temperature, direction and composition -arising from both the cathode and anode regions- as well as in the effect they have on the incident electron beam. These low-density plasmas can only be measured with diagnostics that measure spectroscopically in the ultraviolet and X ray range as well as with advanced interferometric techniques such as Thomson scattering, faraday rotation and phase contrast imaging. The University of New Mexico has recently developed computational models that demonstrate the capability to design frequency adjustable sources with lower outgassing of neutrals. Iteratively coupling the results from the above-mentioned diagnostics to these simulations is the path forward for producing effective HPM weapons with long pulse and high repetition rates. Computational models that take into account full 3 dimensional effectively sized sources, as well as the evolution of complex adsorbed molecules from birth to electron beam neutralization are very intensive and have pushed the computational hardware to its limits. In order to make a paradigm shift in field deployable HPM weapons with long high energy pulses we must follow this iterative process whereby experiment feeds state of the art simulation that then feeds engineering decisions that then yield effective HPM field deployable weapons.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Mar 05, 2022
- Source ID
- N000142212226
Entities
People
- S. Portillo
Organizations
- Office of Naval Research
- United States Navy
- University of New Mexico