IPAC2014 - List of Authors (Galyamin, S.N.)

Paper	Title	Page
WEPRO006	Beam-driven Terahertz Source based on Open Ended Waveguide with a Dielectric Layer	1949
	A.V. Tyukhtin, S.N. Galyamin, V.V. Vorobev Saint-Petersburg State University, Saint-Petersburg, Russia S.P. Antipov Euclid TechLabs, LLC, Solon, Ohio, USA S. Baturin LETI, Saint-Petersburg, Russia
	Funding: Work is supported by the Grant of the President of Russian Federation (MK-273.2013.2) and the Russian Foundation for Basic Research (Grant No. 12-02-31258). Electromagnetic waves with frequencies from 0.1 THz to 10 THz (usually called the Terahertz gap) are of great importance for a number of scientific and practical applications. Different techniques are known allowing generating these frequencies. However, a current trend of physics and industry is to fill this gap with more powerful and efficient sources. For example, recent experiments have shown promising THz generation in dielectric loaded structures. Developing this area, we consider the THz emitting scheme where an ultrarelativistic charge exits the open end of a cylindrical waveguide with a dielectric layer and produces THz waves in a form of Cherenkov radiation. The end of the waveguide is supposed to be either orthogonal to the structure axis or skewed. To obtain THz frequencies from waveguides with centimeter or millimeter radii, we consider high order modes. We present typical field patterns (in the Fraunhofer zone) and show that the aperture of the vacuum channel gives, as a rule, the main contribution. We also give simple expressions for the angle of the main pattern lobe. S. Antipov et al., Appl. Phys. Lett. 100, 132910 (2012).
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-WEPRO006
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THPME156	Convergent Cherenkov Radiation from Dielectric Targets	3626
	S.N. Galyamin, E.S. Belonogaya, A.V. Tyukhtin, V.V. Vorobev Saint-Petersburg State University, Saint-Petersburg, Russia E.S. Belonogaya LETI, Saint-Petersburg, Russia
	Funding: Work was supported by the Grant of the President of Russian Federation (No. 273.2013.2). Cherenkov radiation is a convenient tool for charged particle detection and bunch diagnostics. However, due to the complexity of real radiator geometry, different approximate techniques are elaborated for investigation of excited radiation. Here we develop recently reported* approximate method for calculating Cherenkov radiation of a charge flying near a dielectric target having two main boundaries (the first interacts with a charge field and the second mainly refracts a generated radiation). We focus on cases where the radiation outside the target is convergent and use two methods for field investigation: ray optical technique and aperture integration technique. First, we deal with the case of a conical target with a vacuum channel. Under certain conditions, this radiation is concentrated near the line being the symmetry axis of the target. Second, we find the specific shape of the target that concentrates radiation in a small vicinity of given point (focus). Such targets can be used for improvement of detectors and bunch diagnostics systems based on Cherenkov effect. A.P. Potylitsyn et al., Diffraction Radiation from Relativistic Particles, STMP 239 (Springer, 2010). *E.S. Belonogaya, A.V. Tyukhtin, S.N. Galyamin, Phys. Rev. E, 87, 043201 (2013).
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-THPME156
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THPME157	Radiation of a Charged Particle Bunch Moving in the Presence of Planar Wire Structure	3629
SUSPSNE081	use link to see paper's listing under its alternate paper code
	V.V. Vorobev, S.N. Galyamin, A.V. Tyukhtin Saint-Petersburg State University, Saint-Petersburg, Russia
	Funding: Work was supported by "Dynasty" Foundation, the Grant of the President of Russian Federation (No. 273.2013.2) and the Russian Foundation for Basic Research (Grant No. 12-02-31258). The structure under consideration represents a set of long thin parallel wires which are placed in a plane with fixed spacing. The wires can exhibit a limited conductivity. If the period of the structure is much less than the typical wavelength, the structure’s influence can be described with help of the averaged boundary conditions. The main attention is given to the case when the bunch flies through the grid in the orthogonal direction. Radiation of charged particle bunch which have small transversal size and limited longitudinal one is studied. Analytical expressions for volume and surface waves are given for the bunches with arbitrary longitudinal profile. A separate analysis is performed for the particular case of the plane which is ideally conducting in only one direction. It is shown that the surface wave is similar, in some way, to the radiation field of the bunch moving in a wire metamaterial. It is demonstrated that the detection of surface waves can be used to estimate the longitudinal sizes of bunches. Typical numerical results for bunches of different shapes and structures with different parameters are given. M.I. Kontorovich et al, Electrodynamics of Grid Structures (Moscow, 1987). ** V.V. Vorobev, A.V. Tyukhtin, Phys. Rev. Let., 108, 184801 (2012).
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-THPME157
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Paper

Title

Page

Beam-driven Terahertz Source based on Open Ended Waveguide with a Dielectric Layer

1949

A.V. Tyukhtin, S.N. Galyamin, V.V. Vorobev
Saint-Petersburg State University, Saint-Petersburg, Russia
S.P. Antipov
Euclid TechLabs, LLC, Solon, Ohio, USA
S. Baturin
LETI, Saint-Petersburg, Russia

Funding: Work is supported by the Grant of the President of Russian Federation (MK-273.2013.2) and the Russian Foundation for Basic Research (Grant No. 12-02-31258).
Electromagnetic waves with frequencies from 0.1 THz to 10 THz (usually called the Terahertz gap) are of great importance for a number of scientific and practical applications. Different techniques are known allowing generating these frequencies. However, a current trend of physics and industry is to fill this gap with more powerful and efficient sources. For example, recent experiments have shown promising THz generation in dielectric loaded structures*. Developing this area, we consider the THz emitting scheme where an ultrarelativistic charge exits the open end of a cylindrical waveguide with a dielectric layer and produces THz waves in a form of Cherenkov radiation. The end of the waveguide is supposed to be either orthogonal to the structure axis or skewed. To obtain THz frequencies from waveguides with centimeter or millimeter radii, we consider high order modes. We present typical field patterns (in the Fraunhofer zone) and show that the aperture of the vacuum channel gives, as a rule, the main contribution. We also give simple expressions for the angle of the main pattern lobe.
* S. Antipov et al., Appl. Phys. Lett. 100, 132910 (2012).

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-WEPRO006

Export •

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

THPME156

Convergent Cherenkov Radiation from Dielectric Targets

3626

S.N. Galyamin, E.S. Belonogaya, A.V. Tyukhtin, V.V. Vorobev
Saint-Petersburg State University, Saint-Petersburg, Russia
E.S. Belonogaya
LETI, Saint-Petersburg, Russia

Funding: Work was supported by the Grant of the President of Russian Federation (No. 273.2013.2).
Cherenkov radiation is a convenient tool for charged particle detection and bunch diagnostics. However, due to the complexity of real radiator geometry, different approximate techniques are elaborated for investigation of excited radiation*. Here we develop recently reported** approximate method for calculating Cherenkov radiation of a charge flying near a dielectric target having two main boundaries (the first interacts with a charge field and the second mainly refracts a generated radiation). We focus on cases where the radiation outside the target is convergent and use two methods for field investigation: ray optical technique and aperture integration technique. First, we deal with the case of a conical target with a vacuum channel. Under certain conditions, this radiation is concentrated near the line being the symmetry axis of the target. Second, we find the specific shape of the target that concentrates radiation in a small vicinity of given point (focus). Such targets can be used for improvement of detectors and bunch diagnostics systems based on Cherenkov effect.
*A.P. Potylitsyn et al., Diffraction Radiation from Relativistic Particles, STMP 239 (Springer, 2010).
**E.S. Belonogaya, A.V. Tyukhtin, S.N. Galyamin, Phys. Rev. E, 87, 043201 (2013).

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-THPME156

Export •

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

THPME157

Radiation of a Charged Particle Bunch Moving in the Presence of Planar Wire Structure

3629

SUSPSNE081

use link to see paper's listing under its alternate paper code

V.V. Vorobev, S.N. Galyamin, A.V. Tyukhtin
Saint-Petersburg State University, Saint-Petersburg, Russia

Funding: Work was supported by "Dynasty" Foundation, the Grant of the President of Russian Federation (No. 273.2013.2) and the Russian Foundation for Basic Research (Grant No. 12-02-31258).
The structure under consideration represents a set of long thin parallel wires which are placed in a plane with fixed spacing. The wires can exhibit a limited conductivity. If the period of the structure is much less than the typical wavelength, the structure’s influence can be described with help of the averaged boundary conditions*. The main attention is given to the case when the bunch flies through the grid in the orthogonal direction. Radiation of charged particle bunch which have small transversal size and limited longitudinal one is studied. Analytical expressions for volume and surface waves are given for the bunches with arbitrary longitudinal profile. A separate analysis is performed for the particular case of the plane which is ideally conducting in only one direction. It is shown that the surface wave is similar, in some way, to the radiation field of the bunch moving in a wire metamaterial**. It is demonstrated that the detection of surface waves can be used to estimate the longitudinal sizes of bunches. Typical numerical results for bunches of different shapes and structures with different parameters are given.
* M.I. Kontorovich et al, Electrodynamics of Grid Structures (Moscow, 1987).
** V.V. Vorobev, A.V. Tyukhtin, Phys. Rev. Let., 108, 184801 (2012).

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2014-THPME157

Export •

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