Paper  Title  Page 

TUPMY032  Radiation from Open Ended Waveguide with a Dielectric Loading  1617 


Funding: Work is supported by the Grant of the President of Russian Federation (No. 6765.2015.2) and the Grants from Russian Foundation for Basic Research (No. 153220985, 150203913). Terahertz radiation is considered as a promising tool for a number of applications. One possible way to emit THz waves is to pass short electron bunch through a waveguide structure loaded with dielectric*. In our previous papers, we have analyzed this problem in both approximate** and rigorous*** formulation. However, we have encountered certain difficulties with calculations. In the present report, we are starting to develop another rigorous approach based on modematching technique and modified residuecalculus technique. We consider the radiation from the openended dielectrically loaded cylindrical waveguide placed inside regular cylindrical waveguide with larger radius. We present structure of reflected and transmitted modes and typical radiation patterns from the open end of larger radius waveguide. * S. Antipov et al., Appl. Phys. Lett., vol. 100, p. 132910, 2012. ** S.N. Galyamin et al., Opt. Express, vol. 22, No. 8, p. 8902, 2014. *** S.N. Galyamin et al., in Proc. IPAC'15, pp. 25782580. 

DOI •  reference for this paper ※ DOI:10.18429/JACoWIPAC2016TUPMY032  
Export •  reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
TUPMY033  Radiation of Charged Particle Flying into Chiral Isotropic Medium  1620 


Funding: Work is supported by the Grant of the Russian Foundation for Basic Research (No. 153220985). In recent years, the interest to radiation of moving charged particles in media with chiral properties is connected with relatively new and prospective method for diagnostics of biological objects which uses the Cherenkov radiation ' Cherenkov luminescence imaging*. Optical activity (chirality, gyrotropy) is typical or biological matter and is caused by mirrorless structure of molecules. Contrary to such gyrotropic medium as magnetized ionospheric plasma, aforementioned media are isotropic. One distributed model describing the frequency dispersion of isotropic chiral media is Condon model. In this report, we continue the investigation performed in our previous paper** where we dealt with the field produced by uniformly moving charge in infinite chiral isotropic medium. Moreover, we perform generalization of early paper***, where the problem with halfspace was considered in the specific case of slow charge motion. We present typical radiation patterns in vacuum area and corresponding ellipses of polarization which allows determination of the chiral parameter of the medium. * Spinelli A.E. et al. // NIM A. 2011. V. 648. P. S310. ** Galyamin S.N. et al. // Phys. Rev. E. 2013. V. 88. P. 013206. *** Engheta N., Mickelson A.R. // IEEE Trans. AP. 1982. V. 30. P. 1213. 

DOI •  reference for this paper ※ DOI:10.18429/JACoWIPAC2016TUPMY033  
Export •  reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
TUPMY034  On Bunch Diagnostics with use of Surface Waves Generated on Planar Wire Grid  1623 


Funding: Work is supported by the Grant of the President of Russian Federation (No. 6765.2015.2) and the Grants from Russian Foundation for Basic Research (No. 153220985, 150203913). Periodic structures can be used for nondestructive diagnostics of charged particle bunches*. We consider structures which consist of thin conducting parallel wires. It is assumed that the structure period is much less than the typical wavelength under consideration. Therefore the influence of the structure on the electromagnetic field can be described with help of the averaged boundary conditions**. We consider radiation of bunches which move along the grid but transversely to wires. Unlike previous works the bunch is assumed to have essential transversal dimensions along with definite longitudinal charge distribution. In particular we analyze the effect of reflection of the surface wave from the structure edge. For all considered situations, analytical and numerical results demonstrate that analysis of the surface waves allows estimating the size and the shape of the bunch. * A.V. Tyukhtin et al., Phys. Rev. ST AB 17, 122802 (2014); A.V. Tyukhtin et al., Phys. Rev. E 91, 063202 (2015). ** M.I. Kontorovich et al., Electrodynamics of Grid Structures (Moscow, 1987). 

DOI •  reference for this paper ※ DOI:10.18429/JACoWIPAC2016TUPMY034  
Export •  reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
TUPMY035  Shortwavelength Radiation of a Small Charged Bunch in Presence of a Dielectric Prism  1626 


Funding: Work is supported by the Grant from Russian Foundation for Basic Research (No. 150203913). Investigation of radiation of a charged particle bunch in the presence of a large (compared with wavelengths under consideration) dielectric object can be performed using certain approximate methods. We develop here the method based on the known StrattonChu formulae which allows calculating the field everywhere outside the object including the Fresnel and Fraunhofer areas, as well as neighborhoods of focal points*. The main problem considered here consists in investigation of radiation of a small bunch moving along boundary of a dielectric prism or in channel inside a prism. Approximate analytical solutions of the problem are obtained and typical numerical results are given. *S.N. Galyamin and A.V. Tyukhtin, Phys. Rev. Lett. 113, 064802, 2014. 

DOI •  reference for this paper ※ DOI:10.18429/JACoWIPAC2016TUPMY035  
Export •  reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  