Laser-Free RF-Gun as a Powerful THz Source

THz technology has a rapidly growing number of potential applications in solid-state, nuclear physics, medicine, biology, remote sensing, imaging, industry and communications. However, THz radiation facilities based on FELs, electron storage rings, and/or energy recovery linacs are too large, too expensive, and not readily available for a broader community of users to operate it on a flexibly customized, on-demand, and independent basis. In this project we will develop a compact and much less expensive coherent terahertz source that allows generation of high peak and average power. The approach uses microbunching provided by the beam compression in an alpha-magnet, beam pre-bunching in the RF gun, and resonant Cherenkov radiation in a robust radiator. The THz radiation in the source can be accompanied by synchronized, intense, sub-ps bursts of hard X-ray radiation for additional capabilities. The Phase I project has demonstrated feasibility in a proof of concept experiment. In addition, the design of the full prototype system was considered in preparation for Phase II. The main goal of the Phase II is to design and build a prototype of a dedicated THz source delivering over 10 J of outcoupled power within s-scale micropulses using a low-energy (~2 MeV) RF injector with thermionic cathode. During the first year of the Phase II we will design and fabricate the core prototype components and test the system at Idaho Accelerator Center. In the second year of Phase II, the system will be configured with a low-cost RF power system and tested as a stand-alone THz source. Commercial Applications and Other Benefits: The enormously wide range of commercial applications includes container inspection, screening, non-destructive testing, safe imaging, remote sensing, surface defectoscopy, cancer diagnostics, and time-domain spectroscopy. A rapidly growing number of research applications are found in solid-state, nuclear physics, medicine, and biology. The same source can additionally generate intense ultrashort bursts of low-dose hard X-ray radiation to enhance screening capability.