IPAC2016 - List of Authors (Lekomtsev, K.)

Paper	Title	Page
MOPMR040	First Steps Towards a Single-Shot Longitudinal Profile Monitor: Study of the Properties of Coherent Smith-Purcell Radiation Using the Surface Current Model	340
SUPSS069	use link to see paper's listing under its alternate paper code
	H. Harrison, G. Doucas, I.V. Konoplev, A.J. Lancaster JAI, Oxford, United Kingdom A. Aryshev, K. Lekomtsev, M. Shevelev, N. Terunuma, J. Urakawa KEK, Ibaraki, Japan
	Funding: UK STFC, Leverhulme Trust, Photon and Quantum Basic Research Coordinated Development Program (Ministry of Education, Culture, Sports, Science and Technology, Japan)and JSPS KAKENHI. We propose to use the polarization of coherent Smith-Purcell radiation (cSPr) to separate the signal from background radiation in a single-shot longitudinal bunch profile monitor. We compare simulation and experimental results for the degree of polarization of cSPr generated by a grating with a 1mm periodic structure at the LUCX facility, KEK (Japan). Both experiment and simulation show that the majority of the cSPr signal is polarized in the direction parallel to the grating grooves. The degree of polarization predicted by simulation is higher than the measured result, therefore further investigation is needed to resolve this discrepancy.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPMR040
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TUPOW044	Experimental Investigation of THz Smith-Purcell Radiation From Composite Corrugated Capillary	1861
	K. Lekomtsev, A. Aryshev, M. Shevelev, N. Terunuma, J. Urakawa KEK, Ibaraki, Japan A. Ponomarenko, A.A. Tishchenko MEPhI, Moscow, Russia
	Funding: This work was supported by Photon and Quantum Basic Research Coordinated Development Program from the Ministry of Education, Culture, Sports, Science and Technology, Japan. Terahertz part of electromagnetic spectrum has a variety of potential applications ranging from fundamental to security applications. Further advances in development of a linac based, tunable, and narrow band coherent source of THz radiation are very important. Mechanisms of Cherenkov radiation and Smith-Purcell radiation (SPR) [] may be used for generation of THz radiation via coherent emission [, ]. In this report we will present experimental investigations of the SPR generated from the corrugated capillary with a reflector, using the femtosecond multi-bunch electron beam of LUCX accelerator at KEK, Japan [*]. LUCX is capable to generate a train of 4 bunches each with 200 femtosecond (60 micrometer) duration and 200 micrometer transverse size. We will discuss the composite design of the capillary, measurements of the SPR angular distributions and the comparison of these measurements with PIC simulations. In addition, we will discuss SPR spectral characteristics; bunch energy modulation, introduced by the corrugated capillary; and the way in which the bunch spacing changes the spectrum and angular distributions of SPR. K.Lekomtsev et al., NIMB 355 (2015) 164 A. M. Cook et al., PRL 103, (2009) 095003. S. E. Korbly et al., PRL 94, (2005) 054803. ***A. Aryshev, arXiv:1507.03302 [physics.acc-ph]
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-TUPOW044
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THPOW007	Cs2Te Photocathode Response Time Measurements and Femtosecond Comb Electron Beam Generation as a Milestone Towards Pre-Bunched Thz Fel Realization	3941
	A. Aryshev, Y. Honda, K. Lekomtsev, M. Shevelev, N. Terunuma, J. Urakawa KEK, Ibaraki, Japan
	Funding: Photon and Quantum Basic Research Coordinated Development Program from the Ministry of Education, Culture, Sports, Science and Technology, Japan and JSPS KAKENHI: 23226020 and 24654076 Currently there is a rapidly growing demand to increase the brightness of electron beams generated by conventional RF guns as well as to decrease the cost of the injector accelerator system for many research facilities worldwide. To address this demand we investigate one of the most important parameter of the high Q.E. conventional semiconductor Cs2Te photocathode, its response time. It sets the principle limitation for generated bunch length and hence maximum achievable beam brightness of electron diffraction and pre-bunched THz FEL facility's injectors. The experimental investigation was done at KEK: LUCX facility. The Cs2Te photocathode response time better than 250 fs was demonstrated. The generation of 4 micro-bunch comb electron beam with variable time separation as a crucial technology for pre-bunched THz FEL realization was achieved.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-THPOW007
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Paper

Title

Page

First Steps Towards a Single-Shot Longitudinal Profile Monitor: Study of the Properties of Coherent Smith-Purcell Radiation Using the Surface Current Model

340

SUPSS069

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

H. Harrison, G. Doucas, I.V. Konoplev, A.J. Lancaster
JAI, Oxford, United Kingdom
A. Aryshev, K. Lekomtsev, M. Shevelev, N. Terunuma, J. Urakawa
KEK, Ibaraki, Japan

Funding: UK STFC, Leverhulme Trust, Photon and Quantum Basic Research Coordinated Development Program (Ministry of Education, Culture, Sports, Science and Technology, Japan)and JSPS KAKENHI.
We propose to use the polarization of coherent Smith-Purcell radiation (cSPr) to separate the signal from background radiation in a single-shot longitudinal bunch profile monitor. We compare simulation and experimental results for the degree of polarization of cSPr generated by a grating with a 1mm periodic structure at the LUCX facility, KEK (Japan). Both experiment and simulation show that the majority of the cSPr signal is polarized in the direction parallel to the grating grooves. The degree of polarization predicted by simulation is higher than the measured result, therefore further investigation is needed to resolve this discrepancy.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPMR040

Export •

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

TUPOW044

Experimental Investigation of THz Smith-Purcell Radiation From Composite Corrugated Capillary

1861

K. Lekomtsev, A. Aryshev, M. Shevelev, N. Terunuma, J. Urakawa
KEK, Ibaraki, Japan
A. Ponomarenko, A.A. Tishchenko
MEPhI, Moscow, Russia

Funding: This work was supported by Photon and Quantum Basic Research Coordinated Development Program from the Ministry of Education, Culture, Sports, Science and Technology, Japan.
Terahertz part of electromagnetic spectrum has a variety of potential applications ranging from fundamental to security applications. Further advances in development of a linac based, tunable, and narrow band coherent source of THz radiation are very important. Mechanisms of Cherenkov radiation and Smith-Purcell radiation (SPR) [*] may be used for generation of THz radiation via coherent emission [**, ***]. In this report we will present experimental investigations of the SPR generated from the corrugated capillary with a reflector, using the femtosecond multi-bunch electron beam of LUCX accelerator at KEK, Japan [****]. LUCX is capable to generate a train of 4 bunches each with 200 femtosecond (60 micrometer) duration and 200 micrometer transverse size. We will discuss the composite design of the capillary, measurements of the SPR angular distributions and the comparison of these measurements with PIC simulations. In addition, we will discuss SPR spectral characteristics; bunch energy modulation, introduced by the corrugated capillary; and the way in which the bunch spacing changes the spectrum and angular distributions of SPR.
*K.Lekomtsev et al., NIMB 355 (2015) 164
**A. M. Cook et al., PRL 103, (2009) 095003.
***S. E. Korbly et al., PRL 94, (2005) 054803.
****A. Aryshev, arXiv:1507.03302 [physics.acc-ph]

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-TUPOW044

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THPOW007

Cs2Te Photocathode Response Time Measurements and Femtosecond Comb Electron Beam Generation as a Milestone Towards Pre-Bunched Thz Fel Realization

3941

A. Aryshev, Y. Honda, K. Lekomtsev, M. Shevelev, N. Terunuma, J. Urakawa
KEK, Ibaraki, Japan

Funding: Photon and Quantum Basic Research Coordinated Development Program from the Ministry of Education, Culture, Sports, Science and Technology, Japan and JSPS KAKENHI: 23226020 and 24654076
Currently there is a rapidly growing demand to increase the brightness of electron beams generated by conventional RF guns as well as to decrease the cost of the injector accelerator system for many research facilities worldwide. To address this demand we investigate one of the most important parameter of the high Q.E. conventional semiconductor Cs2Te photocathode, its response time. It sets the principle limitation for generated bunch length and hence maximum achievable beam brightness of electron diffraction and pre-bunched THz FEL facility's injectors. The experimental investigation was done at KEK: LUCX facility. The Cs2Te photocathode response time better than 250 fs was demonstrated. The generation of 4 micro-bunch comb electron beam with variable time separation as a crucial technology for pre-bunched THz FEL realization was achieved.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-THPOW007

Export •

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