RuPAC2014 - List of Authors (Toporkov, S.E.)

Paper	Title	Page
WEPSB04	Field Optimization Technique of the Multigap H-mode Resonators	162
	S.E. Toporkov, A.B. Buleiko, M.V. Lalayan MEPhI, Moscow, Russia
	Optimization of the H-mode resonators requires uniform accelerating field distribution on its axes. To realize this task pylons with the holes on its end walls are used in many cases. During applying this technique in case of cavities with low number of periods it was mentioned that the best value of the field flatness was obtained in case of zero gap between end walls of the resonator and the pylon. It means that each pylon has got the electrical contact with one of the end walls of the resonator. For such cavity geometry magnetic field distribution differs from the classical H – resonator: it transforms in one common magnetic flux like in split-coaxial cavities. The analysis of such structures was performed for two types of H-mode resonators: Cross bar H-mode (CH) resonators with working frequency 324MHz and Interdigital H-mode (IH) resonators with working frequency 162MHz. All types of resonators work on the pi-mode and have 9 accelerating gaps. The main stages of E-field flatness optimization inside CH⁻ and IH⁻ cavities are presented at this paper.

WEPSB05	Optimization of Electric Field Distribution Inside Multi-gap CH-Resonator	164
	S.E. Toporkov MEPhI, Moscow, Russia
	This paper presents the results of the electrodynamic modelling of the Crossbar H-mode (CH) resonator. The main goal was to get the uniform accelerating field distribution and to optimize effective shunt impedance. The initial model of the 324 MHz cavity consists of 7 equidistant RF gaps with the period length 46.26 mm. To optimize its electrodynamic characteristics the design contains pylons. Solution of the tuning task consists of several steps. Firstly it was chosen the optimal relation between the holding rod length and the pylon's height. Then the most significant improvement on the E-field distribution was introduced by optimizing the gap between end walls of the resonator and the pylon. The final adjustment of the field distribution and the tuning to the working frequency was performed by means of the holes in the pylon. Correct geometry increases effective shunt impedance from 55 MOhm/m to 80 MOhm/m and improves the field flatness to the 97%. The results of optimization the cavities for different particle velocities with 7,9 and 11 accelerating gaps and different aperture diameter are presented.

THPSC04	Study of Normal Conducting Accelerating Structures for Megawatt Proton Driver Linac	321
	S.M. Polozov, A.E. Aksentyev, A.A. Kalashnikova, T. Kulevoy, M.V. Lalayan, S.E. Toporkov MEPhI, Moscow, Russia
	Funding: This project was supported by the Ministry of Science and Education of Russia under contract No. 14.516.11.0084 The preliminary design of megawatt level proton accelerator-driver is carrying out by collaboration between Russian scientific centers MEPhI, ITEP, Kurchatov Institute. This project was supported in 2013 by the Ministry of Science and Education of Russia. The linac general layout includes RFQ section and section(s) with radiofrequency focusing. The different types of RF focusing were studied due to this project: RF crossed lenses, modified electrodes RFQ, axi-symmetrical RF focusing. All such focusing can be realized by IH-type cavities. The design of segmented vane RFQ (SVRFQ) with coupling windows and IH⁻ and CH-type normal conducting cavities will discuss in the report. All cavities operate on 162 MHz. The main electrodynamics simulation results will present.

THPSC05	Study of Possibility of 600-1000 MeV and 1 MW Proton Driver Linac Development in Russia	324
	S.M. Polozov, A.E. Aksentyev, K.A. Aliev, I.A. Ashanin, Y.A. Bashmakov, A.A. Blinnikov, T.V. Bondarenko, A.N. Didenko, M.S. Dmitriyev, V.V. Dmitriyeva, V.S. Dyubkov, A.M. Fadeev, A. Fertman, M. Gusarova, A.A. Kalashnikova, V.I. Kaminsky, E. Khabibullina, Yu.D. Kliuchevskaia, A.D. Kolyaskin, T. Kulevoy, M.V. Lalayan, S.V. Matsievskiy, V.I. Rashchikov, A.V. Samoshin, E.A. Savin, Ya.V. Shashkov, A.Yu. Smirnov, N.P. Sobenin, S.E. Toporkov, O. Verjbitskiy, A.V. Ziiatdinova, V. Zvyagintsev MEPhI, Moscow, Russia P.N. Alekseev, V.A. Nevinnitsa NRC, Moscow, Russia V.F. Batyaev, G. Kropachev, D.A. Liakin, S.V. Rogozhkin, Y.E. Titarenko ITEP, Moscow, Russia S. Stark INFN/LNL, Legnaro (PD), Italy
	Funding: This project was supported by the Ministry of Science and Education of Russia under contract No. 14.516.11.0084 Alternative nuclear energetic's technologies as fast reactors and accelerating driven systems (ADS) are necessary to solve a number of problems as U-238 or thorium fuel reactor and nuclear wastes transmutation. ADS subcritical system should consist of megawatt-power proton accelerator, neutron producing target and breeder. A number of ADS projects are under development in EU, Japan, USA, China, S.Korea at present. Superconducting linacs or their complexes with high energy storage synchrotron are under design in main projects as a megawatt power proton beam driver. In Russian Federation the complex design for accelerator-driver was carried down more than ten years ago. The new approach to the ADS complex is now under development in framework of the project carried out by collaboration between Russian scientific centers MEPhI, ITEP, Kurchatov Institute. This project was supported in 2013 by the Ministry of Science and Education of Russia. A brief results observation for accelerator part of the project is presented in report. It includes accelerator-driver general layout, beam dynamics simulation, electrodynamics simulations of accelerating cavities and analysis of technological background in Russia.

Paper

Title

Page

Field Optimization Technique of the Multigap H-mode Resonators

162

S.E. Toporkov, A.B. Buleiko, M.V. Lalayan
MEPhI, Moscow, Russia

Optimization of the H-mode resonators requires uniform accelerating field distribution on its axes. To realize this task pylons with the holes on its end walls are used in many cases. During applying this technique in case of cavities with low number of periods it was mentioned that the best value of the field flatness was obtained in case of zero gap between end walls of the resonator and the pylon. It means that each pylon has got the electrical contact with one of the end walls of the resonator. For such cavity geometry magnetic field distribution differs from the classical H – resonator: it transforms in one common magnetic flux like in split-coaxial cavities. The analysis of such structures was performed for two types of H-mode resonators: Cross bar H-mode (CH) resonators with working frequency 324MHz and Interdigital H-mode (IH) resonators with working frequency 162MHz. All types of resonators work on the pi-mode and have 9 accelerating gaps. The main stages of E-field flatness optimization inside CH⁻ and IH⁻ cavities are presented at this paper.

WEPSB05

Optimization of Electric Field Distribution Inside Multi-gap CH-Resonator

164

S.E. Toporkov
MEPhI, Moscow, Russia

This paper presents the results of the electrodynamic modelling of the Crossbar H-mode (CH) resonator. The main goal was to get the uniform accelerating field distribution and to optimize effective shunt impedance. The initial model of the 324 MHz cavity consists of 7 equidistant RF gaps with the period length 46.26 mm. To optimize its electrodynamic characteristics the design contains pylons. Solution of the tuning task consists of several steps. Firstly it was chosen the optimal relation between the holding rod length and the pylon's height. Then the most significant improvement on the E-field distribution was introduced by optimizing the gap between end walls of the resonator and the pylon. The final adjustment of the field distribution and the tuning to the working frequency was performed by means of the holes in the pylon. Correct geometry increases effective shunt impedance from 55 MOhm/m to 80 MOhm/m and improves the field flatness to the 97%. The results of optimization the cavities for different particle velocities with 7,9 and 11 accelerating gaps and different aperture diameter are presented.

THPSC04

Study of Normal Conducting Accelerating Structures for Megawatt Proton Driver Linac

321

S.M. Polozov, A.E. Aksentyev, A.A. Kalashnikova, T. Kulevoy, M.V. Lalayan, S.E. Toporkov
MEPhI, Moscow, Russia

Funding: This project was supported by the Ministry of Science and Education of Russia under contract No. 14.516.11.0084
The preliminary design of megawatt level proton accelerator-driver is carrying out by collaboration between Russian scientific centers MEPhI, ITEP, Kurchatov Institute. This project was supported in 2013 by the Ministry of Science and Education of Russia. The linac general layout includes RFQ section and section(s) with radiofrequency focusing. The different types of RF focusing were studied due to this project: RF crossed lenses, modified electrodes RFQ, axi-symmetrical RF focusing. All such focusing can be realized by IH-type cavities. The design of segmented vane RFQ (SVRFQ) with coupling windows and IH⁻ and CH-type normal conducting cavities will discuss in the report. All cavities operate on 162 MHz. The main electrodynamics simulation results will present.

THPSC05

Study of Possibility of 600-1000 MeV and 1 MW Proton Driver Linac Development in Russia

324

S.M. Polozov, A.E. Aksentyev, K.A. Aliev, I.A. Ashanin, Y.A. Bashmakov, A.A. Blinnikov, T.V. Bondarenko, A.N. Didenko, M.S. Dmitriyev, V.V. Dmitriyeva, V.S. Dyubkov, A.M. Fadeev, A. Fertman, M. Gusarova, A.A. Kalashnikova, V.I. Kaminsky, E. Khabibullina, Yu.D. Kliuchevskaia, A.D. Kolyaskin, T. Kulevoy, M.V. Lalayan, S.V. Matsievskiy, V.I. Rashchikov, A.V. Samoshin, E.A. Savin, Ya.V. Shashkov, A.Yu. Smirnov, N.P. Sobenin, S.E. Toporkov, O. Verjbitskiy, A.V. Ziiatdinova, V. Zvyagintsev
MEPhI, Moscow, Russia
P.N. Alekseev, V.A. Nevinnitsa
NRC, Moscow, Russia
V.F. Batyaev, G. Kropachev, D.A. Liakin, S.V. Rogozhkin, Y.E. Titarenko
ITEP, Moscow, Russia
S. Stark
INFN/LNL, Legnaro (PD), Italy

Funding: This project was supported by the Ministry of Science and Education of Russia under contract No. 14.516.11.0084
Alternative nuclear energetic's technologies as fast reactors and accelerating driven systems (ADS) are necessary to solve a number of problems as U-238 or thorium fuel reactor and nuclear wastes transmutation. ADS subcritical system should consist of megawatt-power proton accelerator, neutron producing target and breeder. A number of ADS projects are under development in EU, Japan, USA, China, S.Korea at present. Superconducting linacs or their complexes with high energy storage synchrotron are under design in main projects as a megawatt power proton beam driver. In Russian Federation the complex design for accelerator-driver was carried down more than ten years ago. The new approach to the ADS complex is now under development in framework of the project carried out by collaboration between Russian scientific centers MEPhI, ITEP, Kurchatov Institute. This project was supported in 2013 by the Ministry of Science and Education of Russia. A brief results observation for accelerator part of the project is presented in report. It includes accelerator-driver general layout, beam dynamics simulation, electrodynamics simulations of accelerating cavities and analysis of technological background in Russia.