Status of the Source of Polarized Ions (March 2013) V.V. Fimushkin, A.D. Kovalenko, L.V. Kutuzova, Yu.V. Prokofichev Joint Institute for Nuclear Research, Dubna A.S. Belov, V.N. Zubets, A.V. Turbabin Institute for Nuclear Research of Russian Academy of Sciences, Moscow

General view of the NICA facility SPI & linac MPD Spin Physics Detector (SPD) The expected luminosity of polarized beams is planned at the level of ( ) cm -2 ·s -1 The new flagship JINR project in high energy nuclear physics, NICA (Nuclotron-based Ion Collider fAcility), aimed at the study of phase transitions in strongly interacting nuclear matter at the highest possible baryon density, was put forward in 2006

The main purpose of the SPI-project is to increase the intensity of the accelerated polarized beams at the JINR Accelerator Complex up to d/pulse

The SPI-project assumes the development of the source using charge-exchange ionizer Nearly resonant charge-exchange reactions for production of polarized protons & deuterons are: H 0 + D + H + + D 0 D 0 + H + D + + H 0 ~ 5 · cm 2 The design output current of the SPI is up to 10 mA for D + ( H + ) The D + polarization will be up to 90% of the maximal vector (±1) & tensor (+1,-2) polarization

The SPI-project includes the following stages: - -development of the high-intensity Source of Polarized Ions - -complete tests of the SPI - -modification of the linac pre-accelerator platform & power station - -remote control system (console of linac) of the SPI under the high voltage - -SPI & Linac runs with polarized beam and polarization measurements at the linac output

NEW SOURCE OF POLARIZED IONS (DEUTERONS) D2D2 H2H2 D + D 2 D D D 0 + H + D + + H 0

The basic equipment for the SPI is already purchased: Pump, Turbo-V 3K-T, 2300 l/s H2, 2400 l/s He - 2 item Pump, Turbo-V 2K-G, 1600 l/s N2 - 2 item Fore pump Dry scroll pump type TriScroll 600 Inverter, 30m³/h - 2 item Cryocooler, Single Stage Cryodyne Refrigeration System, Model 350 will provide 40 watts of heat lift at 77K Pressure measurement system, MaxiGauge TPG256A controller for 6 gauges ABS Power supply Sorensen DCS 8-350E (8V, 350A, 3 kW) Power supply Sorensen SGI40X375C-1CAA (40V, 375A, 15kW) - ABS sextupole Power supply Sorensen DCS E (12V, 250A, 3 kW) - ionizer solenoid Power supply Sorensen XG (8V, 200A, 1.6 kW) Power supply Sorensen DCS20-150E (20V, 150A, 3 kW) - bending magnet of the ionizer Power supply Sorensen XG (40V, 42A, 1680 W) - ABS arc source ABS&IONIZER Signal Generator SMB100A with option - 1 item SMB-B102 9kHz – 2.2 GHz High Frequency Generator HG1462C - 2 items 100kHz-400MHz Power amplifier FLG-15CA, 0.7GHz-3GHz - 1 item Power amplifier FLH-20B, 20MHz-1000MHz - 2 items Power Supply ZUP-10-20, 0-10V, 0-20A – 4 items High voltage power supply HCP item 0-30 kV, 0-10 mA, positive High voltage power supply HCP items 0-30 kV, 0-10 mA, negative IONIZER RF - units ABS

High-voltage isolation transformer 35kVA 160kVDC Stewart isolation transformer Electrostatically shielded amps/35 kva- 160 kvdc isolation between input and output Input: 400 vac Delta / 3 phase / Hz Output: 3 Single Phase outputs each at 230v intended to be connected in Wye configuration yielding 3 phase at 400v between lines Total Weight: 600 kg

The NUCLOTRON feature is that the injection is possible only for positive ions Therefore it is expedient to use the source of positive polarized deuterium ions Note: The highest intensity of the beam is reached for positive polarized ion sources with charge-exchange plasma ionizer and the storage cell SPI-source assumes to convert the charge-exchange ionizer of CIPIOS into the ionizer using storage of polarized deuterium atoms and production of positive polarized deuterons by resonance charge-exchange in the hydrogen plasma

The ionizer with storage of polarized atoms for the SPI allows - increase intensity of the polarized D + beam, - reduce emittance of the polarized beam - considerably reduce H 2 + ion current which is difficult to be separated from polarized D + due to similar mass of the ions.

INR RAS polarized ion source atomic beam-type source with resonant charge-exchange plasma ionizer and with a storage cell in the charge-exchange region (Belov et. al. INR RAS, 1986, 1999) H 0 + D + H + + D 0 11 mA of H + 80 % polarization has been obtained from the INR source from ABC storage cell plasma source

Status of the ABS development Atomic Beam Source (ABS) of the SPI has been assembled and tested at INR RAS The pulse density of atomic D beam at the distance of 150 cm from the cooling nozzle outlet is 2.5 · at/cm 3 at the most probable velocity of 1.5 ·10 +5 cm/s Functional tests of WFT&MFT of the RF cells of the nuclear polarization of deuterium (hydrogen) atoms were performed

Preliminary tests results Atomic D & H beam intensities are measured Nozzle temperature was scanned over a range of 16…80 K The optimum nozzle temperature is about 27 K The optimum feed rate is about mbar · l/pulse The averaged beam intensities are estimated as I D = 8 · at/s I H = 5 · at/s

RFT scheme and deuteron polarization HFT between 6poles HFT after 6poles Final D hfs P Z P ZZ MFT 3 4 WFT 1 4, 2 3 3, MFT 3 4 SFT 2 6 1, MFT 1 4 SFT 3 5 2, MFT 1 4 SFT 2 6 3,6 0 +1

Tests of the WFT Hydrogen atoms Deuterium atoms D atoms WFT efficiency – 0.95H atoms WFT efficiency – 0.90

Tests of the MFT 3 4 mode 1 4 mode Deuterium atoms

The work which is carried out at JINR includes - -assembly and tests of the charge-exchange plasma ionizer, including the storage cell in the ionization volume - -optimization of the ion-optical system up to 25 keV and transport of the high-current deuteron beam - -long-term tests of the SPI with the storage cell in the ionizer - polarimetry of the accelerated beam at the output of linac It is necessary to develop control system components for primary analysis & data acquisition and for fiber optic system of data transmission

General view of SPI ( September 2012 ) ABS Charge-exchange plasma ionizer

SPI view from the dissociator chamber to RFQ

Перечень работ по SPI на стенде кор.203А в г Подготовка установки к испытаниям: монтаж контура заземления по периметру помещения отв. Н.В. Семин монтаж выхлопной линии вакуумной откачки установки из помещения отв. А.А. Цветков монтаж контура водяного охлаждения установки отв. В.В. Фимушкин установка пневмозатвора Ду 63 между ИПА и ЗПИ с автономным контуром сжатого воздуха отв. В.В. Фимушкин - монтаж и разводка оборудования в электротехнических шкафах отв. В.В. Фимушкин -монтаж и подключение Stewart isolation transformer 35kVA 160kVDC отв. Н.В. Семин -электротехнические и радиотехнические работы отв. В.В. Фимушкин -разработка и изготовление блоков питания импульсного генератора плазмы для SPI, включая время пролетный масс-спектрометр (заключение Договора с ИЯИ РАН на 2013 г) отв. В.В. Фимушкин, А.С. Белов -заключение Договора с ИЯИ РАН на 2013 г. на совместное проведение испытаний SPI в ОИЯИ отв. В.В. Фимушкин, А.С. Белов

Планируемые комплексные испытания SPI на стенде кор.203А в 2013 г. - работа с электродуговым источником дейтериевой плазмы, запуск ЗПИ I -II квартал 2013 г. отв. В.В. Фимушкин, А.С. Белов -запуск и испытания SPI в режиме получения поляризованных протонов I – II квартал 2013 г. отв. В.В. Фимушкин, А.С. Белов -работа с электродуговым источником водородной плазмы, запуск ЗПИ с накопительной ячейкой III квартал 2013 г. отв. В.В. Фимушкин, А.С. Белов - запуск и испытания SPI в режиме получения поляризованных дейтронов III – IV квартал 2013 г. отв. В.В. Фимушкин, А.С. Белов

Перечень работ по SPI на форинжекторе Лу-20 в г.г. -модернизация высоковольтной платформы в соответствии с выбранной схемой -монтаж и подключение Stewart isolation transformer 35kVA 160kVDC -контур водяного охлаждения SPI на базе выбранного WATER CHILLER -стыковка установки и разработка элементов согласования SPI с ускорительной трубкой, RFQ – системой -разработка и установка магнитных линз на входе в Лу-20, исключающих прецессию спина -система дистанционного контроля и управления SPI на высоком потенциале с пульта управления Лу-20 -электронная система согласования работы SPI с Лу-20 и физическими установками (метки поляризации, положение оси квантования в характерных точках по ускорительному тракту и т.д.)

Расчёт сдвоенной линзы

Поляриметрия Lamb-shift polarimeter – поляриметр низких энергий (25 кэВ) с использованием Cs или Na – мишени. Конфигурируется с SPI в режиме on line Breit-Rabi поляриметр проведение измерений эффективности и наладка ячеек ВЧ-переходов с помощью времяпролетного масс-спектрометра в камере источника плазмы Поляриметр на выходе Лу-20

General layout of the Cryogenic Polarized Atomic Jet Source as the NICA Absolute Polarimeter

Summary & Outlook Work was carried out at INR of RAS (Moscow) and testing of the ABS systems was finished in July 2012 In August 2012, the ABS was transported from the INR of RAS (Moscow) and assembled at JINR All-inclusive SPI-testing will be carried out in at JINR