IPAC2018 - List of Authors (Savilov, A.V.)

Paper	Title	Page
THPMF012	Tapered Flying Radiofrequency Undulator	4059
	S.P. Antipov, S.V. Kuzikov, A. Liu Euclid TechLabs, LLC, Solon, Ohio, USA S.V. Kuzikov, A.V. Savilov, A.A. Vikharev IAP/RAS, Nizhny Novgorod, Russia
	Funding: DOE SBIR DE-SC0017145 The x-ray free electron laser (x-FEL) efficiency, measured as a fraction of the electron beam power converted into light, is typically below 0.1% for most of the x-FEL facilities presently in operation. Undulator tapering techniques can be used to improve the conversion efficiency by 1-2 orders of magnitude. However at present there are no robust tapered undulator x-FEL schemes operating at 10% efficiency. In this paper we report on the development of tapered radiofrequency (RF) undulator. An RF undulator is a microwave waveguide in which strong RF field is excited that interacts with a charged particle beam forcing it to radiate coherent x-rays while undergoing a wiggling motion. RF undulators are attractive for use in x-FELs due to their large beam aperture and a short undulator period. Strongly tapered RF undulators (with tapering of a wavelength) due to non-resonant trapping regime allow keeping high overall XFEL efficiency being driven by laser plasma accelerated beams usually having high enough current but large energy spread (1-10%).
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-THPMF012
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THPMF050	High-Efficient XFELO Based on Optical Resonator with Self-Modulated Q-Factor	4172
	S.V. Kuzikov, A.V. Savilov, A.A. Vikharev IAP/RAS, Nizhny Novgorod, Russia S.P. Antipov, S.V. Kuzikov Euclid TechLabs, LLC, Solon, Ohio, USA
	In this paper we describe an efficient XFELO having a new non-stationary out-coupling scheme. It consists of two undulator sections placed inside optical cavity. The first section is a conventional uniform undulator and the second one is a tapered undulator. At start time point X-ray radiation is mostly produced by the uniform section. Mirrors of XFELO's optical resonator are designed so that diffraction Q-factor reaches the highest value, i.e losses are near zero. As X-ray power increases the tapered undulator begins to contribute more to radiation power. However a portion of that power misses mirrors of the optical cavity, because those are tuned to confine radiation produced by the first undulator. This process establishes a steady state operation of the XFELO.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-THPMF050
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Page

Tapered Flying Radiofrequency Undulator

4059

S.P. Antipov, S.V. Kuzikov, A. Liu
Euclid TechLabs, LLC, Solon, Ohio, USA
S.V. Kuzikov, A.V. Savilov, A.A. Vikharev
IAP/RAS, Nizhny Novgorod, Russia

Funding: DOE SBIR DE-SC0017145
The x-ray free electron laser (x-FEL) efficiency, measured as a fraction of the electron beam power converted into light, is typically below 0.1% for most of the x-FEL facilities presently in operation. Undulator tapering techniques can be used to improve the conversion efficiency by 1-2 orders of magnitude. However at present there are no robust tapered undulator x-FEL schemes operating at 10% efficiency. In this paper we report on the development of tapered radiofrequency (RF) undulator. An RF undulator is a microwave waveguide in which strong RF field is excited that interacts with a charged particle beam forcing it to radiate coherent x-rays while undergoing a wiggling motion. RF undulators are attractive for use in x-FELs due to their large beam aperture and a short undulator period. Strongly tapered RF undulators (with tapering of a wavelength) due to non-resonant trapping regime allow keeping high overall XFEL efficiency being driven by laser plasma accelerated beams usually having high enough current but large energy spread (1-10%).

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-THPMF012

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPMF050

High-Efficient XFELO Based on Optical Resonator with Self-Modulated Q-Factor

4172

S.V. Kuzikov, A.V. Savilov, A.A. Vikharev
IAP/RAS, Nizhny Novgorod, Russia
S.P. Antipov, S.V. Kuzikov
Euclid TechLabs, LLC, Solon, Ohio, USA

In this paper we describe an efficient XFELO having a new non-stationary out-coupling scheme. It consists of two undulator sections placed inside optical cavity. The first section is a conventional uniform undulator and the second one is a tapered undulator. At start time point X-ray radiation is mostly produced by the uniform section. Mirrors of XFELO's optical resonator are designed so that diffraction Q-factor reaches the highest value, i.e losses are near zero. As X-ray power increases the tapered undulator begins to contribute more to radiation power. However a portion of that power misses mirrors of the optical cavity, because those are tuned to confine radiation produced by the first undulator. This process establishes a steady state operation of the XFELO.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-THPMF050

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)