P.Bagryansky, The 8 th International Conference on Open Magnetic Systems for Plasma Confinement, July 5, CONFINEMENT OF HOT ION PLASMA WITH β=0.6 IN THE GAS DYNAMIC TRAP 1,2 P.A.Bagryansky, 1,2 A.V.Anikeev, 1,2 A.D.Beklemishev, 1,2 A.S.Donin, 1,2 A.A.Ivanov, 2 M.S.Korzhavina, 1,2 Yu.V.Kovalenko, 1 E.P.Kruglyakov, 1 A.A.Lizunov, 1,2 V.V.Maximov, 1,2 S.V.Murakhtin, 1,2 V.V.Prikhodko, 2 E.I.Pinzhenin, 2 A.N.Pushkareva, 1 V.Ya.Savkin, 2 K.V.Zaytsev 1 Budker Institute of Nuclear Physics: akademika Lavrentieva prospect/11, Novosibirsk, Russia, Novosibirsk State University: Pirogova street /2, Novosibirsk, Russia, ,

2 Outline P.Bagryansky, The 8 th International Conference on Open Magnetic Systems for Plasma Confinement, July 5, Introduction; 2.Recent results of machine upgrade; 3.Regimes of operation; 4.Basic plasma parameters; 5.Discussion; 6.Conclusions.

3 The GDT device Mirror-to-mirror distance 7 м Magnetic field at the mid-plane up to 0.35 Т in mirrors up to 14 Т Mirror ratio up to 35 Time of neutral beam operation 5 мс Total neutral beam power up to 5 МW Warm plasma: cm -3, ~200 eV Fast ions (H +,D + ): ~5·10 13 сm -3, 10 keV P.Bagryansky, The 8 th International Conference on Open Magnetic Systems for Plasma Confinement, July 5, 2010 expander beam dump central cell cusp cellplasma dump NBI modules

4 Upgrade of NBI system was completed 8 NBI modules, total NB power – up to 5 MW, =5ms P.Bagryansky, The 8 th International Conference on Open Magnetic Systems for Plasma Confinement, July 5, 2010

5 Total NBI power in reliable regime of operation P, Wt t, ms Energy of H 0, D 0 particles: 22 – 25 keV Measured with special calorimeter system just before plasma column (see poster: S.V.Murakhtin at al., Wednsday July 7) P.Bagryansky, The 8 th International Conference on Open Magnetic Systems for Plasma Confinement, July 5, 2010

6 Upgrade of power supply for magnetic coils Additional capacity battery (C=0.15 F, U=4.5 kV) connected with external mirror coils. B0: 0.3 T 0.35 T R: P.Bagryansky, The 8 th International Conference on Open Magnetic Systems for Plasma Confinement, July 5, 2010

7 Vortex confinement +350 V plasma dump mirror limiter P.Bagryansky, The 8 th International Conference on Open Magnetic Systems for Plasma Confinement, July 5, 2010 V.V.Prikhpdko et al., report OS 2010, Tuesday July 6, 15:30. 1.Shear flows, driven by using the biased end-plates and limiters, in combination with finite-Larmor- radius effects are shown to be efficient to radially confine high-β plasma even with magnetic hill on axis. 2.Interpretation of the observed effects as the vortex confinement, i.e., confinement of the plasma core in the dead-flow zone of the driven vortex, agrees rather well with simulations and experiment. 3.Theoretical scaling laws predict such confinement scheme to be also applicable at higher plasma temperature and density. A.D.Beklemishev, et. al., Fusion Science and Technology, 57, May 2010;

8 Typical «scenario» of experiment Plasma generator Gas fuelling Neutral Beam Injection t, ms Time schedule mirror coil plasma absorber limiter gas puff P.Bagryansky, The 8 th International Conference on Open Magnetic Systems for Plasma Confinement, July 5, 2010

9 Progress in basic plasma parameters: fast ions Upgrade of NBI system and increasing of magnetic field allowed one to increase energy of fast ion population ( 2 kJ instead 1.1 kJ before modernization) Diamagnetism of fast ions vs time in regime with D 0 injection into D plasma P.Bagryansky, The 8 th International Conference on Open Magnetic Systems for Plasma Confinement, July 5, 2010

10 Local diamagnetism B/B v vs W f, D 0 – beams B/B v W f, J B=0.28 T B=0.3 T P.Bagryansky, The 8 th International Conference on Open Magnetic Systems for Plasma Confinement, July 5, 2010 B/B v 0.22 before modernization

11 Estimations: and n f - from equilibrium equation: ( B/B v ) max =0.37 max , =10 keV n сm -3 = P.Bagryansky, The 8 th International Conference on Open Magnetic Systems for Plasma Confinement, July 5, 2010

12 Progress in basic plasma parameters: T e (H 0 beams, H plasma) P.Bagryansky, The 8 th International Conference on Open Magnetic Systems for Plasma Confinement, July 5, 2010 n cm -3, P tr =1.6 MW (35%) T e vs time T e 130 eV before modernization

13 Progress in basic plasma parameters: T e (D 0 beams, D plasma) P.Bagryansky, The 8 th International Conference on Open Magnetic Systems for Plasma Confinement, July 5, 2010 T e vs time t, ms T e, eV T e 150 eV before modernization

14 Regime: H 0 beams, H plasma P.Bagryansky, The 8 th International Conference on Open Magnetic Systems for Plasma Confinement, July 5, 2010 confinement time of fast ions: cm -3, 150 eV ei 1.5 мс – steady-state regime of fast proton confinement is predicted

15 Simple estimation of T e max Confinement of isotropic ions in the magnetic mirror: Mirnov V.V., Tkachenko О.А., rep. BINP particle flux energy flux steady-state energy balance taking into account only longitudinal heat flux T[eV], P h [MW], a[cm], n[10 13 cm -3 ] P.Bagryansky, The 8 th International Conference on Open Magnetic Systems for Plasma Confinement, July 5, 2010

T e vs heat power: experiment and calculations 16 Н 0 – beams, Н – plasma, a=14 cm, R = 33. T e ~ P h 2/3 T e ~ P h 2/7 calculation experiment calculation P h, MW T e, eV P.Bagryansky, The 8 th International Conference on Open Magnetic Systems for Plasma Confinement, July 5, 2010

17 Extrapolation for the projecting Neutron Source P h NS = 22 МW; P h GDT = 1.4 МW; T e GDT = 180 eV. T e NS = T e GDT (P h NS /P h GDT ) 1 keV P.Bagryansky, The 8 th International Conference on Open Magnetic Systems for Plasma Confinement, July 5, 2010

18 Transverse energy losses P.Bagryansky, The 8 th International Conference on Open Magnetic Systems for Plasma Confinement, July 5, 2010 P h = 1.4 МW P || = 1.3 ± 0.2 МW P 0.3 MW (20%) Heat flux on the plasma absorbers was measured by special movable bolometer in regime with H 0 beams

19 Conclusions P.Bagryansky, The 8 th International Conference on Open Magnetic Systems for Plasma Confinement, July 5, Stable plasma confinement with =60% at the steady-state regime was demonstrated; 2.The longitudinal particle and energy loss are in the good agreement with the model of gas dynamic flow of the collisional plasma through the mirrors; 3.The perpendicular heating power loss does not exceed 20% of total plasma heat power ; 4.Results obtained are the essential arguments supporting feasibility of the projecting neutron source based on the gas dynamic trap.

20 How to increase T e ? Outlooks. 1.NBI: increasing of power and time of operation, increasing of magnetic field; 2.Auxiliary heating: ECRH, electron beam; 3.Improvement of longitudinal confinement: ambipolar plugs, electron beam. P.Bagryansky, The 8 th International Conference on Open Magnetic Systems for Plasma Confinement, July 5, 2010

21 Thank you for your attention ! P.Bagryansky, The 8 th International Conference on Open Magnetic Systems for Plasma Confinement, July 5, 2010

П. Багрянский, научная сессия ИЯФ им. Г.И.Будкера, 15 января 2010 г. 22 Амбиполярные пробки: эксперимент с КП (2008 г.) Камера КП: L=30 см, d =70 см. Магнитная система: B 0 =2.4 Тл, B m =5.2 Тл Мишенная плазма: водород, n см -3, T e 90 эВ, a =9 см. Инжекционная система: водород или дейтерий E 0 =20 кэВ, θ=90º, P inj 0.8 МВт, τ inj =4 мс Основные задачи Изучение микронеустойчивостей в плазме с анизотропными горячими ионами Изучение возможности использования КП в качестве амбиполярной пробки для ГДЛ;

П. Багрянский, научная сессия ИЯФ им. Г.И.Будкера, 15 января 2010 г. 23 Амбиполярные пробки: подавление продольного потока ионов Зависимость плотности потока ионов в расширителе от отношения плотности горячих ионов в КП к плотности плазмы в центральном сечении ГДЛ.

П. Багрянский, научная сессия ИЯФ им. Г.И.Будкера, 15 января 2010 г. 24 Вакуумная камера второго КП: финальная стадия обработки

П. Багрянский, научная сессия ИЯФ им. Г.И.Будкера, 15 января 2010 г. 25 Планы 2010 года 1.Детальное изучение удержания частиц и энергии; 2.Изучение равновесия и устойчивости плазмы в режимах с максимальным ; 3.Изучение неустойчивостей; 4.Подготовка и проведение эксперимента с двумя амбиполярными пробками; 5.Подготовка системы СВЧ нагрева плазмы: испытание гиротронов, конструирование трактов ввода СВЧ излучения, проектирование систем питания гиротронов … 6.Модернизация существующих и создание новых диагностик: лазерное рассеяние, активная штарковская спектроскопия, дисперсионный интерферометр, измеритель потенциала плазмы, …