Electron beam applications at Sandia national Laboratories 1.5 MW HAWK facility

The need for ground based missile-scale and air-breathing propulsion test capabilities above Mach 7 led to the reconstruction of the HAWK electron beam accelerator approximately a decade ago. Electron beams were chosen as a source for adding thermal energy to supersonic gas flows to achieve representative temperatures and dynamic gas pressures along the desired flight corridor. Since the first incarnation of HAWK, investigations utilizing the system have spanned electron beam pumped lasers to beam transport development for radiation generation or energy deposition. Early experiments were limited to the use of foil and plasma windows as enablers for beam extraction thereby limiting achievable beam currents and durations. This was followed by modifications to the HAWK system in 2004 accommodating windowless beam extraction with an axial magnetic field. This integrated hardware addition was demonstrated at a beam current of 1.5 A for 5ms durations. Recent experiments have added the new capability of coupling the electron beam into a Magnetohydrodynamic chamber. This paper discusses the HAWK accelerator and the achievements that it has enabled.