Experiments at the GOL-PET facility have shown that injection of a relativistic electron beam at kiloampere current into a magnetized plasma column with strong radial density gradients is accompanied by generation of THz radiation flux which power estimated at the level of several megawatts. Extraction of this flux along the axis of the beam-plasma system is essentially increased in case when the end of the plasma column is separated by a vacuum gap from the wall of a plasma chamber. Results of measuring the spatial and angular properties of such megawatt flux of THz radiation going out from the plasma to an air of the experimental hall are described in our paper.
Spatially-extended high-power Cherenkov masers operating in millimeter wavelength band intended for using in powering systems of Compton-type FELs are under development in collaboration of IAP RAS (Nizhny Novgorod) and BINP RAS (Novosibirsk). Electrodynamic systems of such oscillators are based on 2D periodical slow-wave structures realizing 2D distributed feedback mechanism, allowing for provision of stable narrow-band oscillation regime under conditions of substantial oversize. This novel feedback mechanism is examined for the oscillators of different geometry. Project of cylindrical slow-wave oscillator of such type operating at Ka-band with sub-GW power level was elaborated based on the tubular electron beam at the “Sinus-6” accelerator 0.5 MeV / 5 kA / 20 ns (IAP RAS). Prospect for further increase of the radiation power is studied in W-band planar Cherenkov maser driven by large-size sheet electron beam forming by the “ELMI” accelerator 1 MeV / 7 kA / 3 μs (BINP RAS). Design parameters, key components and results of simulations of these oscillators are presented, status and results of their experimental studies are discussed.
Project of high-power FEL of sub-THz to THz band is under development in collaboration of BINP RAS (Novosibirsk) and IAP RAS (N.Novgorod) based on the linac “LIU-5” 5 MeV / 2 kA / 200 ns. The aim of this project is to achieve sub-GW power level and a record pulse energy content, ~ 10 -100 J in the specified frequency bands. The design parameters and key components of the FEL are discussed. Helical pulsed undulators were elaborated allowing for effective pumping of operating bounce oscillations. New modification of Bragg structures based on the coupling of propagating and quasi-cutoff waves, so-called advanced Bragg structures, and the possibility of its use to compose the FEL electrodynamic system were studied.
We present the selected results of theoretical and experimental investigations of high-performance ultra-thin
metamaterial-inspired absorbers designed for narrow-band operation at subterahertz frequencies and intended for
integration with spectrally-selective bolometric devices. The attainability of values up to 182 for the ratio of the free-space
wavelength to the absorber's thickness is experimentally demonstrated, while realizability of even thinner
structures is shown. The first prototypes of spectrophotometric and imaging detectors with metamaterial-based radiation-sensitive
pixels, utilizing a principle of THz-to-IR conversion, are discussed.
The paper presents the experimental results on generating and transforming the ribbon (3.5 X 130 cm) beam with the electron energy 1 MeV, beam current 70 kA and pulse duration 8 microsecond(s) . The 70% efficiency of the energy transfer from a capacitor storage to the ribbon beam has been achieved. The close value of the efficiency has been obtained for transforming the ribbon beam to the compressed circular one at the optimal conditions. According to the measurements the angular spread of the compressed beam is less than 100.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.