Reconstruction of light and polarized ion beam injection system of JINR Nuclotron-NICA accelerator complex

Reconstruction of light and polarized ion beam injection system of JINR Nuclotron-NICA accelerator complex

The NICA ion collider project at JINR is under development at present. As a part of the project the Nuclotron injector upgrade has been started. The work is provided in cooperation of JINR, MEPhI and ITEP. Up to now the Nuclotron injection system consist of a number of proton and ion sources, the 65...

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Datum:2013
Hauptverfasser: Andreev, V.A., Balabin, A.I., Butenko, A.V., Dyubkov, V.S., Govorov, A.I., Golovensky, B.V., Kobets, V.V., Kolomiets, A.A., Koshelev, V.A., Kovalenko, A.D., Kozlov, A.V., Kropachev, G.N., Kuibeda, R.P., Kulevoy, T.V., Kuzmichev, V.G., Levterov, K.A., Lyakin, D.A., Monchinsky, V.A., Plastun, A.S., Polozov, S.M., Samoshin, A.V., Seleznev, D.N., Seleznev, V.V., Sidorin, A.O., Stasevich, Yu.B., Trubnikov, G.V.
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Sprache:English
Veröffentlicht: Національний науковий центр «Харківський фізико-технічний інститут» НАН України 2013
Schriftenreihe:Вопросы атомной науки и техники
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Состояние действующих и проекты новых ускорителей
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Zitieren:Reconstruction of light and polarized ion beam injection system of JINR Nuclotron-NICA accelerator complex / V.A. Andreev, A.I. Balabin, A.V. Butenko, V.S. Dyubkov, A.I. Govorov, B.V. Golovensky, V.V. Kobets, A.A. Kolomiets, V.A. Koshelev, A.D. Kovalenko, A.V. Kozlov, G.N. Kropachev, R.P. Kuibeda, T.V. Kulevoy, V.G. Kuzmichev, K.A. Levterov, D.A. Lyakin, V.A. Monchinsky, A.S. Plastun, S.M. Polozov, A.V. Samoshin, D.N. Seleznev, V.V. Seleznev, A.O. Sidorin, Yu.B. Stasevich, G.V. Trubnikov // Вопросы атомной науки и техники. — 2013. — № 6. — С. 8-12. — Бібліогр.: 12 назв. — англ.

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spelling irk-123456789-1117782017-01-15T03:03:04Z Reconstruction of light and polarized ion beam injection system of JINR Nuclotron-NICA accelerator complex Andreev, V.A. Balabin, A.I. Butenko, A.V. Dyubkov, V.S. Govorov, A.I. Golovensky, B.V. Kobets, V.V. Kolomiets, A.A. Koshelev, V.A. Kovalenko, A.D. Kozlov, A.V. Kropachev, G.N. Kuibeda, R.P. Kulevoy, T.V. Kuzmichev, V.G. Levterov, K.A. Lyakin, D.A. Monchinsky, V.A. Plastun, A.S. Polozov, S.M. Samoshin, A.V. Seleznev, D.N. Seleznev, V.V. Sidorin, A.O. Stasevich, Yu.B. Trubnikov, G.V. Состояние действующих и проекты новых ускорителей The NICA ion collider project at JINR is under development at present. As a part of the project the Nuclotron injector upgrade has been started. The work is provided in cooperation of JINR, MEPhI and ITEP. Up to now the Nuclotron injection system consist of a number of proton and ion sources, the 650 keV pulsed preinjector and DTL linac LU-20 (Alvarez type). Such system provides injection into Nuclotron of 20 MeV proton and 5 MeV/u (Z/A >0.3) ion beams. The ion beam acceleration is realized at the 2nd harmonic of bunch travelling mode. The 650 kV high-voltage platform will be replaced by new RFQ structure. The R&D of this system is discussed in the report. Results of beam dynamics simulation in RFQ and MEBT between RFQ and LU-20, electrodynamics simula-tion, construction of RFQ resonator, RF feeding system construction will be presented. The RF power system is assembled and tested at equivalent load and RFQ resonator manufacturing is started. В даний час в ОІЯД розробляється і реалізується проект коллайдера важких іонів NICA, а також проводиться необхідна реконструкція «Нуклотрона». Зокрема, співробітниками ОІЯД, МІФІ та ІТЕФ проводиться реконструкція системи інжекції іонного пучка. В даний час система інжекції включає в себе кілька джерел протонів і іонів, імпульсний електростатичний інжектор на 650 кВ і прискорювач Альвареца ЛУ-20. Ця система дозволяє інжектувати в «Нуклотрон» пучки протонів з енергією 20 МеВ і важких іонів з енергією 5 МеВ/нукл. При цьому прискорення іонів у ЛУ-20 виробляється на другий кратності. У результаті реконструкції високовольтний інжектор повинен бути замінений прискорювачем-группірователем з просторово-однорідним квадрупольним фокусуванням (ПОКФ). Розглянуто хід робіт зі створення цього нового прискорювача. Представлено результати моделювання динаміки пучка в резонаторі з ПОКФ і каналі узгодження з ЛУ-20, результати моделювання електродинамічних характеристик прискорюючого резонатора і його конструювання, результати розробки системи високочастотного живлення. В даний час система харчування зібрана і налаштована на еквівалентне навантаження , а резонатор з ПОКФ переданий у виробництво. В настоящее время в ОИЯИ разрабатывается и реализуется проект коллайдера тяжелых ионов NICA, а также проводится необходимая реконструкция «Нуклотрона». В частности, сотрудниками ОИЯИ, МИФИ и ИТЭФ проводится реконструкция системы инжекции ионного пучка. В настоящее время система инжекции включает в себя несколько источников протонов и ионов, импульсный электростатический инжектор на 650 кВ и ускоритель Альвареца ЛУ-20. Эта система позволяет инжектировать в «Нуклотрон» пучки протонов с энергией 20 МэВ и тяжелых ионов с энергией 5 МэВ/нукл. При этом ускорение ионов в ЛУ-20 производится на второй кратности. В результате реконструкции высоковольтный инжектор должен быть заменен ускорителем-группирователем с пространственно-однородной квадрупольной фокусировкой (ПОКФ). Рассмотрен ход работ по созданию этого нового ускорителя. Представлены результаты моделирования динамики пучка в резонаторе с ПОКФ и канале согласования с ЛУ-20, результаты моделирования электродинамических характеристик ускоряющего резонатора и его конструирования, результаты разработки системы высокочастотного питания. В настоящее время система питания собрана и настроена на эквивалентную нагрузку, а резонатор с ПОКФ передан в производство. 2013 Article Reconstruction of light and polarized ion beam injection system of JINR Nuclotron-NICA accelerator complex / V.A. Andreev, A.I. Balabin, A.V. Butenko, V.S. Dyubkov, A.I. Govorov, B.V. Golovensky, V.V. Kobets, A.A. Kolomiets, V.A. Koshelev, A.D. Kovalenko, A.V. Kozlov, G.N. Kropachev, R.P. Kuibeda, T.V. Kulevoy, V.G. Kuzmichev, K.A. Levterov, D.A. Lyakin, V.A. Monchinsky, A.S. Plastun, S.M. Polozov, A.V. Samoshin, D.N. Seleznev, V.V. Seleznev, A.O. Sidorin, Yu.B. Stasevich, G.V. Trubnikov // Вопросы атомной науки и техники. — 2013. — № 6. — С. 8-12. — Бібліогр.: 12 назв. — англ. 1562-6016 PACS: 29.17.w, 29.27.Bd http://dspace.nbuv.gov.ua/handle/123456789/111778 en Вопросы атомной науки и техники Національний науковий центр «Харківський фізико-технічний інститут» НАН України
institution Digital Library of Periodicals of National Academy of Sciences of Ukraine
collection DSpace DC
language English
topic Состояние действующих и проекты новых ускорителей
Состояние действующих и проекты новых ускорителей
spellingShingle Состояние действующих и проекты новых ускорителей
Состояние действующих и проекты новых ускорителей
Andreev, V.A.
Balabin, A.I.
Butenko, A.V.
Dyubkov, V.S.
Govorov, A.I.
Golovensky, B.V.
Kobets, V.V.
Kolomiets, A.A.
Koshelev, V.A.
Kovalenko, A.D.
Kozlov, A.V.
Kropachev, G.N.
Kuibeda, R.P.
Kulevoy, T.V.
Kuzmichev, V.G.
Levterov, K.A.
Lyakin, D.A.
Monchinsky, V.A.
Plastun, A.S.
Polozov, S.M.
Samoshin, A.V.
Seleznev, D.N.
Seleznev, V.V.
Sidorin, A.O.
Stasevich, Yu.B.
Trubnikov, G.V.
Reconstruction of light and polarized ion beam injection system of JINR Nuclotron-NICA accelerator complex
Вопросы атомной науки и техники
description The NICA ion collider project at JINR is under development at present. As a part of the project the Nuclotron injector upgrade has been started. The work is provided in cooperation of JINR, MEPhI and ITEP. Up to now the Nuclotron injection system consist of a number of proton and ion sources, the 650 keV pulsed preinjector and DTL linac LU-20 (Alvarez type). Such system provides injection into Nuclotron of 20 MeV proton and 5 MeV/u (Z/A >0.3) ion beams. The ion beam acceleration is realized at the 2nd harmonic of bunch travelling mode. The 650 kV high-voltage platform will be replaced by new RFQ structure. The R&D of this system is discussed in the report. Results of beam dynamics simulation in RFQ and MEBT between RFQ and LU-20, electrodynamics simula-tion, construction of RFQ resonator, RF feeding system construction will be presented. The RF power system is assembled and tested at equivalent load and RFQ resonator manufacturing is started.
format Article
author Andreev, V.A.
Balabin, A.I.
Butenko, A.V.
Dyubkov, V.S.
Govorov, A.I.
Golovensky, B.V.
Kobets, V.V.
Kolomiets, A.A.
Koshelev, V.A.
Kovalenko, A.D.
Kozlov, A.V.
Kropachev, G.N.
Kuibeda, R.P.
Kulevoy, T.V.
Kuzmichev, V.G.
Levterov, K.A.
Lyakin, D.A.
Monchinsky, V.A.
Plastun, A.S.
Polozov, S.M.
Samoshin, A.V.
Seleznev, D.N.
Seleznev, V.V.
Sidorin, A.O.
Stasevich, Yu.B.
Trubnikov, G.V.
author_facet Andreev, V.A.
Balabin, A.I.
Butenko, A.V.
Dyubkov, V.S.
Govorov, A.I.
Golovensky, B.V.
Kobets, V.V.
Kolomiets, A.A.
Koshelev, V.A.
Kovalenko, A.D.
Kozlov, A.V.
Kropachev, G.N.
Kuibeda, R.P.
Kulevoy, T.V.
Kuzmichev, V.G.
Levterov, K.A.
Lyakin, D.A.
Monchinsky, V.A.
Plastun, A.S.
Polozov, S.M.
Samoshin, A.V.
Seleznev, D.N.
Seleznev, V.V.
Sidorin, A.O.
Stasevich, Yu.B.
Trubnikov, G.V.
author_sort Andreev, V.A.
title Reconstruction of light and polarized ion beam injection system of JINR Nuclotron-NICA accelerator complex
title_short Reconstruction of light and polarized ion beam injection system of JINR Nuclotron-NICA accelerator complex
title_full Reconstruction of light and polarized ion beam injection system of JINR Nuclotron-NICA accelerator complex
title_fullStr Reconstruction of light and polarized ion beam injection system of JINR Nuclotron-NICA accelerator complex
title_full_unstemmed Reconstruction of light and polarized ion beam injection system of JINR Nuclotron-NICA accelerator complex
title_sort reconstruction of light and polarized ion beam injection system of jinr nuclotron-nica accelerator complex
publisher Національний науковий центр «Харківський фізико-технічний інститут» НАН України
publishDate 2013
topic_facet Состояние действующих и проекты новых ускорителей
url http://dspace.nbuv.gov.ua/handle/123456789/111778
citation_txt Reconstruction of light and polarized ion beam injection system of JINR Nuclotron-NICA accelerator complex / V.A. Andreev, A.I. Balabin, A.V. Butenko, V.S. Dyubkov, A.I. Govorov, B.V. Golovensky, V.V. Kobets, A.A. Kolomiets, V.A. Koshelev, A.D. Kovalenko, A.V. Kozlov, G.N. Kropachev, R.P. Kuibeda, T.V. Kulevoy, V.G. Kuzmichev, K.A. Levterov, D.A. Lyakin, V.A. Monchinsky, A.S. Plastun, S.M. Polozov, A.V. Samoshin, D.N. Seleznev, V.V. Seleznev, A.O. Sidorin, Yu.B. Stasevich, G.V. Trubnikov // Вопросы атомной науки и техники. — 2013. — № 6. — С. 8-12. — Бібліогр.: 12 назв. — англ.
series Вопросы атомной науки и техники
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fulltext ISSN 1562-6016. ВАНТ. 2013. №6(88) 8 RECONSTRUCTION OF LIGHT AND POLARIZED ION BEAM INJECTION SYSTEM OF JINR NUCLOTRON-NICA ACCELERATOR COMPLEX V.A. Andreev 2 , A.I. Balabin 2 , A.V. Butenko 3 , V.S. Dyubkov 1 , A.I. Govorov 3 , B.V. Golovensky 3 , V.V. Kobets 3 , A.A. Kolomiets 2 , V.A. Koshelev 2 , A.D. Kovalenko 3 , A.V. Kozlov 2 , G.N. Kropachev 2 , R.P. Kuibeda 2 , T.V. Kulevoy 1,2 , V.G. Kuzmichev 2 , K.A. Levterov 3 , D.A. Lyakin 2 , V.A. Monchinsky 3 , A.S. Plastun 1 , S.M. Polozov 1 , A.V. Samoshin 1 , D.N. Seleznev 2 , V.V. Seleznev 3 , A.O. Sidorin 3 , Yu.B. Stasevich 2 , G.V. Trubnikov 3 1 National Research Nuclear University “Moscow Engineering Physics Institute”, Moscow, Russia E-mail: SMPolozov@mephi.ru; 2 Institute of Theoretical and Experimental Physics, Moscow, Russia E-mail: kulevoy@itep.ru; 3 Joint Institute for Nuclear Research, Dubna, Moscow region, Russia The NICA ion collider project at JINR is under development at present. As a part of the project the Nuclotron in- jector upgrade has been started. The work is provided in cooperation of JINR, MEPhI and ITEP. Up to now the Nu- clotron injection system consist of a number of proton and ion sources, the 650 keV pulsed preinjector and DTL linac LU-20 (Alvarez type). Such system provides injection into Nuclotron of 20 MeV proton and 5 MeV/u (Z/A >0.3) ion beams. The ion beam acceleration is realized at the 2nd harmonic of bunch travelling mode. The 650 kV high-voltage platform will be replaced by new RFQ structure. The R&D of this system is discussed in the report. Results of beam dynamics simulation in RFQ and MEBT between RFQ and LU-20, electrodynamics simula- tion, construction of RFQ resonator, RF feeding system construction will be presented. The RF power system is assembled and tested at equivalent load and RFQ resonator manufacturing is started. PACS: 29.17.w, 29.27.Bd INTRODUCTION The new accelerator complex NICA (Nuclotron- based Ion Collider facility) is now under development and construction at JINR. The injection system of the operating heavy ion superconducting accelerator Nuclo- tron is upgrade is planned. Moreover, construction of the booster ring, the collider rings and two particle de- tectors (MPD and SPD) is in progress (Fig. 1). Fig. 1. Scheme of NICA facility: 1 – light and polarized ion sources and “old” Alvarez-type linac LU-20; 2 – ESIS source and new linac; 3 – Synchrophasotron yoke, Booster and Nuclotron; 4 – Nuclotron beam lines and fixed target experiments area; 5 – the collider rings; 6 – SPD; 7 – MPD General goal of the NICA project is experimental studies of both hot and dense strongly interacting bary- onic matter and spin physics in collisions of heavy ions and polarized protons and deuterons [1 - 4]. The first task of the program requires heavy ion collisions in the energy range of NNS = 4…11 GeV at an average lumi- nosity of L 1∙1027 cm-2c-1 for 197Au79+ nuclei. The polar- ized beams mode is proposed to be used in the energy range of collision energy of protons S =12…27 GeV and deuterons NNS = 4…13.8 GeV (2…5.9 GeV/u ion kinetic energy) at an avarege luminosity L 1∙1031 cm-2c-1. The NICA project assumed to operate using two in- jectors [5]: the Alvarez-type linac LU-20 as injector for light ions, polarized protons and deuterons and a new linac HILac for heavy ions. The Electron String Ion Source (ISIS) is planned for ion beam generation meanwhile the Source of Polarized (SPI) is planned for polarized proton and deuteron beam generation [6]. Up- grade of LU-20 front end is described. 1. LU-20 INJECTION LINAC UPGRADE PROGRAM Alvarez-type DTL linac LU-20 used as the Nuclo- tron injector. was put into operation in 1974. It was originally designed as the proton accelerator. Protons can be accelerated by LU-20 from 600 keV to 20 MeV. Later it was modified to accelerate ions with charge-to- mass ratio Z/A>0.3 due to modification of operational mode from L = βλ to 2βλ. That made it possible to ac- celerate also ions up to 5 MeV/u [7]. The pulse transformer with voltage up to 700 kV is now used to feed the accelerating tube of the LU-20 forinjector. The ion sources used up to now and placed at the HV “hot” platform consumes up to 5 kW power, which is provided by feeding station consisting of motor and generator insulated one from the other with wood shaft. Power consumption of the new ion sources is ~15 kW for ESIS and ~25 kW for SPI [6]. Such power level can not be provided by the existing system. The new fore-injector will be based on radio-frequency quadrupole linac (RFQ). Replacement electrostatic tube with RFQ will allow to decrease potential of the “hot” platform and to use the insulation transformer to feed the sources. High voltage (up to 150 kV) DC power supply will be used to provide necessary electric poten- mailto:kulevoy@itep.ru ISSN 1562-6016. ВАНТ. 2013. №6(88) 9 tial. Installation of two separate RFQ (for Z/A=1 and Z/A=0.3…0.5) can be made to cover the necessary range of particles charge-to-mass ratio [6]. The RFQ section parameters are shown in Table 1. Table 1 The forinjector design parameters Forinjector Input Z/A 1.0 0.5 0.3 Injection energy, keV ≤150 61.8 103 Maximum current, mА 40 20 10 Normalized transverse emittance, π∙cm∙mrad 0.4 0.2 0.15 Operating frequency, MHz 145.2 Output Output energy, MeV/u 0.631 0.156 0.156 Transmission RFQ, % ≥ 80 ≥85 ≥90 Δp/p, % ≤ 6 ≤ 4 ≤ 4 Normalized transverse emittance, π∙cm∙mrad ≤ 1.0 ≤0.5 ≤ 0.5 Resonator length, m ≤ 3 ≤ 3 ≤ 3 Voltage at electrodes, kV 126 84 140 The new RFQ linac project is performed in collabo- ration of JINR, MEPhI and ITEP. The beam dynamics simulation, RF resonator simulation, construction and drawing and RF system development and manufacturing are finished till present. The accelerating resonator is now under manufacturing at VNIITP (Snezhinsk). Let we discussed the main R&D results. 2. BEAM DINAMICS IN RFQ RESONATOR The results of beam dynamics simulation and RFQ channel parameters definition are discussed in detail later. It wills very complex goal to achieve the project parameters because of very low output energy and high injection beam emittance and leads to non conventional RFQ linac design. Table 2 Beam dynamics simulation parameters Z/A 0.3 0.5 Injection and output energy, keV/u 31…155 Normalized acceptance, π∙cm∙mrad 0.5 Normalized emittance, π∙cm∙mrad 0.15 0.2 Limiting current (simulated), mA 190 114 Transverse oscillations phase ad- vance, deg 26.5 Longitudinal oscillations phase advance, deg 23.5 Synchronous phase, deg -90…-40 Output pulse spectrum, % ± 2.5 Averaged distance of electrode from the axis, mm 6.5 Electrodes modulation coefficient 1.28 Aperture radius, mm 5.7 Cells number 194 Linac total length, mm 2070 Current transmission coefficient, % without/with buncher 91/ 93 88/ 89 Transverse emittance growth, without/with buncher 1.33/ 1.25 1.18/ 1.14 Longitudinal emittance growth, without/with buncher 2.89/ 1.96 2.89/ 1.61 The scheme of accelerating-focusing RFQ channel consists of matching, bunching, main accelerating and debunching sub-sections. The main channel and beam parameters were defined by analytical model and beam dynamics simulation and are presented in Table 2. The parameters of channel were choosing by the method proposed in [8]. The beam dynamics simulations were done using codes RFQDYN, DYNAMION [9] developed at ITEP and LIDOS [10] developed at MRTI RAS. Two possi- ble schemes were discussed: without of matching reso- nator (buncher) before RFQ resonator and with such buncher. The results of simulation are presented in Table 2 and Figs. 2, 3. Fig. 2. Output particles distribution in transverse and longi- tudinal phase planes, Z/A=0.3, without matching resonator Fig. 3. Output particles distribution in transverse and lon- gitudinal phase planes, Z/A=0.3, with matching resonator It is clear that the matching resonator sufficiently decrease the output beam emittance. The current limit of the structure was also defined by simulation (Fig. 4). Fig. 4. Current transmission versus injection current ISSN 1562-6016. ВАНТ. 2013. №6(88) 10 3. RFQ – LU-20 MATCHING CHANNEL Matched channel should provide total beam re- capturing in the next section. But in our case it is very serious problem because of long transport base between the RFQ end and the first LU-20 drift tube (correspond- ing to the LU-20 vacuum system parameters) and low injection energy of LU-20. Seven different matching schemes were simulated to obtain high recapturing effi- ciency. The most common matching scheme is present- ed in Fig. 5. Such scheme includes up to three bunchers (before RFQ R, after RFQ B1 and into vacuum seal of LU-20 B2). Two magnet quadrupole triplets (Q1-Q6) are used for transverse beam matching. Fig. 5. Matching system scheme It was shown by simulation that the optimal match- ing can be achieved using only R and B1 without B2 buncher. Up to 90% of injected into RFQ ions for Z/A=0.3 and 87% for Z/A=0.5 are effectively transport- ed to the first LU-20 drift tube and 79% for Z/A=0.3 and 71% for Z/A=0.5 will injected into measured LU-20 acceptance. Transverse losses are very low in transport and all of them are due to longitudinal bunch size en- largement. Using of the third buncher no gives no some advantages but makes very seriously complex vacuum and RF systems much more complicated. 4. RFQ RESONATOR The four-vane resonator with displaced magnetic coupling windows [11] was chosen for NICA the RFQ design. Operating frequency is of 145.2 MHz and such frequency is defined by the LU-20 main resonator oper- ating frequency. The simulations of electrodynamics characteristics of the resonator were done using CST Studio Suite code. The models of one resonant cell and 3D model of whole resonator (Fig. 6) were designed and studied. The resonator consists of nine resonant cells, seven of them are identical and two are the end cells with modified coupling windows. Fig. 6. RFQ resonator model The simulations were directed to match the cells to the operating frequency and to minimize the deviation of RF field amplitude. Both problems were solved and the amplitude deviation is not higher than ±0.25% (Fig. 7). The tolerances of the electrodes manufacturing must be less than ±25 µm (±0.39% of averaged aperture radius) whereas and the constructional errors are two times lower of them. Fig. 7. Inter-electrode voltage distribution along resonator Unfortunately, the simulation can not guarantee that the resonator will have exact value of operating frequen- cy. That is why the resonator has been simulated for a little bit higher resonant frequency (146.6 MHz) in order to find operating frequency by means of enlargement of the windows size. The resonator has been simulated for a little bit higher resonant frequency (146.6 MHz). After first assembling of resonator for electrodes adjusting the frequency measurements will be carried out. According to the measured result the final electrodes windows di- mensions will be defined to provide the resonance fre- quency from region 149.9≤f≤145.1 MHz. The resonator parameters after optimization are presented in Table 3. Table 3 RFQ resonator parameters Length of electrodes, mm 2070 Total length of resonator, mm 2190 Diameter of resonator, mm 400 Transverse size of coupling window, mm 62 Longitudinal size of coupling window, mm 288 Resonant frequency before tuning, MHz 146.6 Operating frequency, MHz 145.2 Dipole mode frequency, MHz 156.4 Voltage at electrodes, kV 125 Q-factor 9300 RF loses, kW 200 RF field amplitude deviation, % < 0.5 Transverse component of RF field devia- tion, % <±0.18 Maximal electric field on surface, MV/m 24 Fig. 8. Model of RFQ resonator with plungers and RF couplers The fine operating frequency tuning can be done us- ing two plungers (tuners) which are constructively ISSN 1562-6016. ВАНТ. 2013. №6(88) 11 placed in the middle of resonator (Fig. 8). The frequen- cy sensitivity to the plunger motion is about 7 kHz/mm. Hence, 50mm movement of the plungers will allow to tune the frequency in 300 kHz range. 5. RFQ RESONATOR DESIGN AND MANUFACTURING The RFQ resonator engineering design was done and the drawings were designed as well (see 3D general view in Fig. 9). For the moment the resonator manufac- turing is started at All-Russian Research Institute of Technical Physics (Snezhinsk) and expected to be fin- ished by the end of 2013. Fig. 9. 3D general view RFQ resonator 6. RF POWER SYSTEM The design the RF power system is discussed more detailed in [12]. The LU-20 resonator is operating in self-excitation mode. This regime demands higher tolerances of RF field stability for LU-20 and RFQ resonators and to higher quality of automatic phase control system. RFQ resonator RF power system consists of two amplifier channels for RFQ resonator and for buncher. High power systems include of low power master gen- erator based on solid state preamplifier, first preamplifi- er based on four GI-39B tubes and high power final amplifying stage based on GI-27AM triode. Buncher RF power system consists of solid state preamplifier and two stages based on GI-39B tubes be- cause of low power necessary. The control system should provide the RF field phase shift between DTL and RFQ resonators better than that one degree. The amplifying stage based on GI-39B tube was tested to define maximal output power at operating fre- quency. The maximum power is equal to 30…35 kW with 150 µs RF pulse length. It is necessary to fed about 50 kW to excite the GI-27. Four pre-amplifying cas- cades based on GI-39 were manufactured and the com- biner was designed. The measured output pulse power Pn, consumed power P0 and efficiency η versus anode potential Ua are shown in Fig. 10. Maximal amplification coefficient is equal to 8.5 and peak measured power is limited by 400 kW. The high power pulse modulator was manufactured to form anode potentials. Power system is manufactured, tested and is ready to routine operation. The photo of RF power system is shown in Fig. 11. Fig. 10. Output pulse power Pn, consumed power P0 and efficiency η versus anode potential Fig. 11. Photo of RF power system CONCLUSIONS The reconstruction of light ion and polarized protons and deuterons beam injection system for Nuclotron- NICA accelerator complex is in progress. It is expected that high-voltage 700 kV platform, which is now used to feed the accelerating tube of Alvarez type linac pre- injector will replaced by RFQ section. The section should to bunch and to accelerate beams of ions with charge-to-mass ratio Z/A>0.3. This project is realized in cooperation o JINR, MEPhI and ITEP and was started in 2011. The beam dynamics in RFQ and in matching system between of new RFQ and LU-20 was studied in detail. It was shown that up to 90% for Z/A=0.3 and 87% for Z/A=0.5 of ions are effectively transported to the first LU-20 drift tube and 79% for Z/A=0.3 and 71% for Z/A=0.5 are recaptured by LU-20. Using of matching resonator before RFQ and integrated debuncher into ISSN 1562-6016. ВАНТ. 2013. №6(88) 12 RFQ provides the low emittance growth in RFQ and transport channel: lower than 25% for transverse emit- tance and lower than two times for longitudinal one. The RFQ resonator based on known scheme using unsymmetrical coupling windows was designed. Tuning system was designed and simulated also. The RF field amplitude deviation is not higher than ±0.25% of the averaged value. RF power system for RFQ and bunchers feeding is designed, manufactured and tested. The operating out- put power is equal to 400 kW which is about two times higher than is necessary for RFQ resonator according to simulation. The RFQ resonator engineering design was done and now the structure is under manufacture at VNIITF. It is planned to finish the manufacturing in 2013. REFERENCES 1. V. Kekelidze, A. Kovalenko, R. Lednicky, V. Matveev, I. Meshkov, A. Sorin, G. Trubnikov // Proc. of 36th International Conference for High En- ergy Physics, ICHEP'12. 2. G. Trubnikov, N. Agapov, V. Alexandrov, et al. // Proc. of IPAC’10. 2010, p. 693. 3. O. Kozlov, H. Khodzhibagiyan, S. Kostromin, et al. // Proc. of IPAC’11. 2011, p. 1108. 4. G. Trubnikov et al. // Proc. of ICHEP'12. 5. A.V. Butenko, E.E. Donets, E.D. Donets, et al. // Proc. of IPAC’13. 2013, p. 3915. 6. A.V. Butenko et al. // Pepan Lett. JINR. 2012, v. 9, № 4-5, p. 654. 7. A.M. Baldin et al. // Proc. of LINAC’96. 1996, p. 352. 8. E.A. Wadlinger // Proc. of PAC’85.1985, p. 2596. 9. A.A. Kolomiets et al. // Proc. of EPAC’98.1998, p. 1201. 10. B.I. Bondarev, A.P. Durkin, et al. // AIP Conf. Proc. 297. Computational accelerator physics. 1993, p. 377. 11. V.A. Andreev, G. Parisi // Proc. of PAC’93.1993, p. 3124. 12. V.G. Kuzmichev, A.V. Kozlov, Yu.B. Stasevich, et al. The RF system for RFQ-injector of linac LU-20 // Problems of Atomic Science and Technology. Series “Nuclear Physics Investigations” (this issue), p. 79-81. Article received 04.09.2013 РЕКОНСТРУКЦИЯ СИСТЕМЫ ИНЖЕКЦИИ ПУЧКА ЛЕГКИХ И ПОЛЯРИЗОВАННЫХ ИОНОВ УСКОРИТЕЛЬНОГО КОМПЛЕКСА «НУКЛОТРОН-NICA» В.А. Андреев, А.И. Балабин, А.В. Бутенко, В.С. Дюбков, А.И. Говоров, Б.В. Головенский, В.В. Кобец, А.А. Коломиец, В.А. Кошелев, А.Д. Коваленко, А.В. Козлов, Г.Н. Кропачев, Р.П. Куйбеда, Т.В. Кулевой, В.Г. Кузмичев, К.А. Левтеров, Д.А. Лякин, В.А. Мончинский, А.С. Пластун, С.М. Полозов, А.В. Самошин, Д.Н. Селезнев, В.В. Селезнев, А.О. Сидорин, Ю.Б. Стасевич, Г.В. Трубников В настоящее время в ОИЯИ разрабатывается и реализуется проект коллайдера тяжелых ионов NICA, а также проводится необходимая реконструкция «Нуклотрона». В частности, сотрудниками ОИЯИ, МИФИ и ИТЭФ проводится реконструкция системы инжекции ионного пучка. В настоящее время система инжекции включает в себя несколько источников протонов и ионов, импульсный электростатический инжектор на 650 кВ и ускоритель Альвареца ЛУ-20. Эта система позволяет инжектировать в «Нуклотрон» пучки прото- нов с энергией 20 МэВ и тяжелых ионов с энергией 5 МэВ/нукл. При этом ускорение ионов в ЛУ-20 произ- водится на второй кратности. В результате реконструкции высоковольтный инжектор должен быть заменен ускорителем-группирователем с пространственно-однородной квадрупольной фокусировкой (ПОКФ). Рас- смотрен ход работ по созданию этого нового ускорителя. Представлены результаты моделирования динами- ки пучка в резонаторе с ПОКФ и канале согласования с ЛУ-20, результаты моделирования электродинами- ческих характеристик ускоряющего резонатора и его конструирования, результаты разработки системы вы- сокочастотного питания. В настоящее время система питания собрана и настроена на эквивалентную нагрузку, а резонатор с ПОКФ передан в производство. РЕКОНСТРУКЦІЯ СИСТЕМИ ІНЖЕКЦІЇ ПУЧКА ЛЕГКИХ І ПОЛЯРИЗОВАНИХ ІОНІВ ПРИСКОРЮВАЛЬНОГО КОМПЛЕКСУ «НУКЛОТРОН-NICA» В.А. Андрєєв, А.І. Балабін, А.В. Бутенко, В.С. Дюбков, А.І. Говоров, Б.В. Головенський, В.В. Кобець, А.А. Коломієць, В.А. Кошелєв, А.Д. Коваленко, А.В. Козлов, Г.Н. Кропачов, Р.П. Куйбеда, Т.В. Кулевий, В.Г. Кузмічов, К.А. Левтеров, Д.А. Лякін, В.А. Мончинський, А.С. Пластун, С.М. Полозов, А.В. Самошин, Д.Н. Селезньов, В.В. Селезньов, А.О. Сідорін, Ю.Б. Стасевич, Г.В. Трубников В даний час в ОІЯД розробляється і реалізується проект коллайдера важких іонів NICA, а також прово- диться необхідна реконструкція «Нуклотрона». Зокрема, співробітниками ОІЯД, МІФІ та ІТЕФ проводиться реконструкція системи інжекції іонного пучка. В даний час система інжекції включає в себе кілька джерел протонів і іонів, імпульсний електростатичний інжектор на 650 кВ і прискорювач Альвареца ЛУ-20. Ця сис- тема дозволяє інжектувати в «Нуклотрон» пучки протонів з енергією 20 МеВ і важких іонів з енергією 5 МеВ/нукл. При цьому прискорення іонів у ЛУ-20 виробляється на другий кратності. У результаті реконст- рукції високовольтний інжектор повинен бути замінений прискорювачем-группірователем з просторово- однорідним квадрупольним фокусуванням (ПОКФ). Розглянуто хід робіт зі створення цього нового приско- рювача. Представлено результати моделювання динаміки пучка в резонаторі з ПОКФ і каналі узгодження з ЛУ-20, результати моделювання електродинамічних характеристик прискорюючого резонатора і його конс- труювання, результати розробки системи високочастотного живлення. В даний час система харчування зіб- рана і налаштована на еквівалентне навантаження , а резонатор з ПОКФ переданий у виробництво.

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