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1. Deuterium–tritium plasmas in novel regimes in the Tokamak Fusion Test Reactor

Author

J. Mcchesney, E. J. Strait, S. H. Batha, R. E. Bell, Harold P. Furth, D.K. Owens, V. Yavorski, H. H. Duong, I. Semenov, A. Kumar, J. S. Kim, Michael A. Beer, Stanley Kaye, Leonid E. Zakharov, Masaaki Yamada, E.D. Fredrickson, K. L. Wong, A. von Halle, D.C. McCune, M.G. Bell, Larry R. Grisham, A. V. Krasilnikov, E. Ruskov, W. Stodiek, R. O. Dendy, J. C. Hosea, P. C. Efthimion, Guoyong Fu, M. Hughes, G. A. Navratil, A. Belov, N. T. Lam, Robert Budny, B.P. LeBlanc, Hyeon K. Park, J. Manickam, T. Stevenson, G. L. Schmidt, W. Park, James R. Wilson, G. Mckee, J. Machuzak, Richard Majeski, Manfred Bitter, H. W. Herrmann, M. Sasao, D. R. Ernst, J. Callen, Chio-Zong Cheng, R. K. Fisher, Yoshio Nagayama, S. A. Sabbagh, S. D. Scott, S. von Goeler, F. M. Levinton, Nikolai Gorelenkov, K. W. Hill, G. Rewoldt, D. R. Mikkelsen, R. T. Walters, William Tang, R.J. Hawryluk, G. Schilling, S. F. Paul, E. J. Synakowski, S. S. Medley, Nathaniel J. Fisch, M. Williams, B. Rice, K. M. McGuire, Roscoe White, A. T. Ramsey, J. D. Strachan, T. Senko, G. Taylor, B. Breizman, H. Takahashi, S. Bernabei, R. Kaita, G. A. Wurden, W. A. Houlberg, D. Mueller, B. C. Stratton, Michael E. Mauel, Michael W Kissick, A. L. Roquemore, C.H. Skinner, P. Phillips, V.Ya. Goloborod'ko, S. Cauffman, M. C. Zarnstorff, William Dorland, J. Hogan, E. Mazzucato, D. L. Jassby, S. V. Mirnov, F. C. Jobes, M. H. Redi, M. Okabayashi, J. Kesner, Kenneth M. Young, W. W. Heidbrink, Dale Meade, J. H. Rogers, M. E. Thompson, S.N. Reznik, M. Phillips, Gregory W. Hammett, H. Berk, C. E. Bush, R. J. Fonck, H. Evenson, N. L. Bretz, Z. Chang, D.K. Mansfield, Raffi Nazikian, R. Wieland, Stewart Zweben, B. Hooper, H.W. Kugel, David Johnson, M. P. Petrov, D. S. Darrow, M. C. Herrmann, C. Ludescher, Choong-Seock Chang, P. H. LaMarche, C. K. Phillips, Shoujun Wang, B. Grek, and M. Osakabe

Subjects
Physics, Tokamak, Magnetic confinement fusion, Plasma, Fusion power, Condensed Matter Physics, Instability, law.invention, Ion, Physics::Plasma Physics, law, Electric current, Atomic physics, Tokamak Fusion Test Reactor
Abstract

Experiments in the Tokamak Fusion Test Reactor (TFTR) have explored several novel regimes of improved tokamak confinement in deuterium-tritium (D-T) plasmas, including plasmas with reduced or reversed magnetic shear in the core and high-current plasmas with increased shear in the outer region (high-l{sub i}). New techniques have also been developed to enhance the confinement in these regimes by modifying the plasma-limiter interaction through in-situ deposition of lithium. In reversed-shear plasmas, transitions to enhanced confinement have been observed at plasma currents up to 2.2 MA (q{sub a} {approx} 4.3), accompanied by the formation of internal transport barriers, where large radial gradients develop in the temperature and density profiles. Experiments have been performed to elucidate the mechanism of the barrier formation and its relationship with the magnetic configuration and with the heating characteristics. The increased stability of high-current, high-l{sub i} plasmas produced by rapid expansion of the minor cross-section, coupled with improvement in the confinement by lithium deposition has enabled the achievement of high fusion power, up to 8.7 MW, with D-T neutral beam heating. The physics of fusion alpha-particle confinement has been investigated in these regimes, including the interactions of the alphas with endogenous plasma instabilities and externally applied waves in the ion cyclotron range of frequencies. In D-T plasmas with q{sub 0} > 1 and weak magnetic shear in the central region, a toroidal Alfven eigenmode instability driven purely by the alpha particles has been observed for the first time. The interactions of energetic ions with ion Bernstein waves produced by mode-conversion from fast waves in mixed-species plasmas have been studied as a possible mechanism for transferring the energy of the alphas to fuel ions.

Published
1997
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2. Review of deuterium–tritium results from the Tokamak Fusion Test Reactor

Author

V. Garzotto, A. Nagy, V. Arunasalam, D. S. Darrow, P. C. Efthimion, A. Janos, V. Zavereev, M.G. Bell, Guoyong Fu, Larry R. Grisham, J. A. Murphy, M. Caorlin, Choong-Seock Chang, Harold P. Furth, J. C. Hosea, J. L. Anderson, R. A. Hulse, David Johnson, D. L. Jassby, R. Rossmassler, K. M. Young, B.P. LeBlanc, Richard Majeski, G. Pearson, G. Coward, M. P. Petrov, I. Semenov, Darin Ernst, Jay Kesner, R. Pysher, Manfred Bitter, R. Marsala, B. McCormack, J. Swanson, M. Williams, H.H. Duong, H. H. Towner, E. Perry, M. Viola, J. Stencel, M. Osakabe, M. McCarthy, D. Long, S. D. Scott, K. L. Wong, J. Machuzak, M. Kalish, Hyeon K. Park, D.C. McCune, N. Fromm, Stewart Zweben, R. T. Walters, W. Tighe, J. R. Timberlake, Z. Chang, G. Schilling, K. M. McGuire, R. E. Bell, P. Alling, E. Ruskov, G. A. Wurden, Michael Loughlin, E. Fredd, Cris W. Barnes, Michael E. Mauel, R. Newman, M. Oldaker, E. J. Synakowski, C. E. Bush, M. Sasao, P. H. LaMarche, C. K. Phillips, R. Camp, H.W. Kugel, M. H. Redi, S. H. Batha, J. Ongena, M. Norris, D.K. Owens, G Rewoldt, R. Durst, Dale Meade, M. Murakami, Nikolai Gorelenkov, K. W. Hill, J. H. Rogers, Gregory R. Hanson, David A Rasmussen, K. Wright, M. C. Zarnstorff, B. Grek, S. Yoshikawa, Roscoe White, T. Senko, G. Labik, H. Takahashi, S. Raftopoulos, S. Ramakrishnan, C. Gentile, H. Evenson, A. L. Qualls, J. McChesney, J. Winston, R. Wester, A. T. Ramsey, M. Hughes, Gerald Navratil, Robert Budny, D. R. Mikkelsen, J. D. Strachan, R. Sissingh, B. C. Stratton, E.D. Fredrickson, William Dorland, T. Stevenson, G. Ascione, H. W. Herrmann, S.A. Sabbagh, R. J. Fonck, L. Dudek, George McKee, J. Collins, W. Blanchard, J. Schivell, R. Scillia, T. Fujita, J.A. Snipes, S. Cauffman, M. E. Thompson, G. Martin, J. Gioia, S. V. Mirnov, A. von Halle, J. DeLooper, D. Ashcroft, John B Wilgen, C. Vannoy, J. Stevens, J. Kamperschroer, C. Ancher, L. C. Johnson, D. Roberts, R. Daugert, W. Park, F. M. Levinton, Gregory W. Hammett, M. Tuszewski, Nathaniel J. Fisch, J. W. Anderson, S. Sesnic, N. T. Lam, William Tang, Chio-Zong Cheng, Glenn Bateman, R. J. Hawryluk, E. Mazzucato, C.H. Skinner, F. C. Jobes, H. Hsuan, Earl Marmar, Michael A. Beer, Masaaki Yamada, R. Fisher, Paul Woskov, J.L. Terry, T. O’Connor, J. Gilbert, E. Lawson, R. Persing, S. F. Paul, D. Loesser, W. W. Heidbrink, G. Barnes, N. L. Bretz, D. Voorhees, W. Stodiek, R. O. Dendy, M. Cropper, G. Renda, P. B. Parks, D. Mueller, Kenji Tobita, A. Martin, S. S. Medley, G. L. Schmidt, G. Taylor, A. L. Roquemore, James R. Wilson, S. von Goeler, J. Levine, H. Adler, S. Pitcher, H. Anderson, Raffi Nazikian, C. Brunkhorst, R. Wieland, J. Chrzanowski, M. Phillips, D.K. Mansfield, and H. Carnevale

Subjects
Nuclear physics, Physics, Thermonuclear fusion, Tokamak, Lawson criterion, law, Nuclear fusion, Magnetic confinement fusion, Fusion power, Condensed Matter Physics, Tokamak Fusion Test Reactor, Inertial confinement fusion, law.invention
Abstract

After many years of fusion research, the conditions needed for a D–T fusion reactor have been approached on the Tokamak Fusion Test Reactor (TFTR) [Fusion Technol. 21, 1324 (1992)]. For the first time the unique phenomena present in a D–T plasma are now being studied in a laboratory plasma.The first magnetic fusion experiments to study plasmas using nearly equal concentrations of deuterium and tritium have been carried out on TFTR. At present the maximum fusion power of 10.7 MW, using 39.5 MW of neutral‐beam heating, in a supershot discharge and 6.7 MW in a high‐βp discharge following a current rampdown. The fusion power density in a core of the plasma is ≊2.8 MW m−3, exceeding that expected in the International Thermonuclear Experimental Reactor (ITER) [Plasma Physics and Controlled Nuclear Fusion Research (International Atomic Energy Agency, Vienna, 1991), Vol. 3, p. 239] at 1500 MW total fusion power. The energy confinement time, τE, is observed to increase in D–T, relative to D plasmas, by 20% and the ni(0) Ti(0) τE product by 55%. The improvement in thermal confinement is caused primarily by a decrease in ion heat conductivity in both supershot and limiter‐H‐mode discharges. Extensive lithium pellet injection increased the confinement time to 0.27 s and enabled higher current operation in both supershot and high‐βp discharges. Ion cyclotron range of frequencies (ICRF) heating of a D–T plasma, using the second harmonic of tritium, has been demonstrated. First measurements of the confined alpha particles have been performed and found to be in good agreement with TRANSP [Nucl. Fusion 34, 1247 (1994)] simulations. Initial measurements of the alpha ash profile have been compared with simulations using particle transport coefficients from He gas puffing experiments. The loss of alpha particles to a detector at the bottom of the vessel is well described by the first‐orbit loss mechanism. No loss due to alpha‐particle‐driven instabilities has yet been observed. D–T experiments on TFTR will continue to explore the assumptions of the ITER design and to examine some of the physics issues associated with an advanced tokamak reactor.

Published
1995
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3. Preparations for deuterium–tritium experiments on the Tokamak Fusion Test Reactor*

Author

V. Mastrocola, D. Wong, B. C. Stratton, G. Martin, William Tang, D. Monticello, P. Snook, C.H. Skinner, Yu. I. Pavlov, H. Carnevale, Richard Majeski, H. Anderson, H. Hsuan, Earl Marmar, Dale Meade, J. H. Rogers, J. Kamperschroer, C. Ancher, V. Garzotto, M. Williams, C. E. Bush, Takeo Nishitani, I. Collazo, R. Ramakrishnan, R. Newman, J. DeLooper, D. Roberts, H. W. Hermann, G. Ascione, E. Fredd, H. H. Towner, Darin Ernst, W. Park, H. Bush, J. Chrzanowski, M. Oldaker, J. W. Anderson, D. Aschroft, K. L. Wong, M. Ulrickson, D.K. Owens, M.G. Bell, S. Raftopoulos, M. Leonard, J. Gioia, J. R. Timberlake, N. T. Lam, A. von Halle, A. Yeun, J. Levine, Leonid E. Zakharov, Jay Kesner, Chio-Zong Cheng, Larry R. Grisham, M. Murakami, D. Loesser, M. J. Laughlin, R. Rossmassler, Liu Chen, J. A. Murphy, T. Golian, G Rewoldt, R. Durst, G. Labik, A. Martin, R. Scillia, M. E. Thompson, S. D. Scott, R.J. Hawryluk, S. S. Medley, John B Wilgen, G. L. Schmidt, Cris W. Barnes, H. Adler, D. R. Mikkelsen, S. Pitcher, F. W. Perkins, R. Sissingh, A. L. Qualls, J. R. Wilson, G. Barnes, T. Stevenson, J. C. Hosea, Raffi Nazikian, C. Brunkhorst, J. Schivell, Glenn Bateman, T. Burgess, V. Arunasalam, D. S. Darrow, P. C. Efthimion, A. L. Roquemore, Michael A. Beer, Guoyong Fu, R. Wieland, R.J. Fonck, E.D. Fredrickson, Gregory W. Hammett, W. Blanchard, S. Kwon, J. Stevens, M. Marchlik, L. C. Johnson, R. Camp, T. Senko, Nikolai Gorelenkov, K. W. Hill, B.P. LeBlanc, D. W. Johnson, William Heidbrink, Hyeon K. Park, R. Daugert, J. Swanson, Masaaki Yamada, David A Rasmussen, M. Sasao, F. M. Levinton, E. Perry, Donald B. Batchelor, J. Stencel, D.C. McCune, D. Long, Manfred Bitter, E. Mazzucato, S. Yoshikawa, K. M. McGuire, S.A. Sabbagh, G. A. Wurden, Michael E. Mauel, L. Dudek, P. Alling, C. Gentile, M. H. Redi, G. Gettelfinger, J. D. Strachan, F. C. Jobes, Paul Woskov, R. C. Goldfinger, G. Renda, B. Grek, D. L. Jassby, J. Snipes, J.L. Terry, D. Mueller, M. Caorlin, C. Vannoy, T. O’Connor, J. Gilbert, G. Taylor, W. Stodiek, M. Cropper, E. Lawson, E. J. Synakowski, A. T. Ramsey, Gerald Navratil, J. L. Anderson, R. Persing, G. R. Hanson, S. F. Paul, R. A. Hulse, G. Pearson, G. Coward, M. P. Petrov, E. F. Jaeger, J. Faunce, M. McCarthy, S. H. Batha, K. Wright, K. M. Young, S.L. Milora, Stewart Zweben, S. Popovichev, S.P. Hirshman, H.W. Kugel, J. Ongena, M. C. Zarnstorff, P.T. Bonoli, A. Nagy, D. J. Hoffman, M. Norris, A. Janos, R. Marsala, M. Osakabe, J. Machuzak, G. Schilling, T. S. Biglow, Harold P. Furth, B. McCormack, H.H. Duong, Z. Chang, P. H. LaMarche, C. K. Phillips, Robert Budny, Steven Cowley, D. E. Mansfield, J. Collins, N. L. Bretz, L. A. Baylor, John Scharer, N. Fromm, and M. J. Gouge

Subjects
Nuclear physics, Tritium illumination, Physics, Lawson criterion, Deuterium, Water cooling, Tritium, Neutron radiation, Fusion power, Condensed Matter Physics, Tokamak Fusion Test Reactor
Abstract

The final hardware modifications for tritium operation have been completed for the Tokamak Fusion Test Reactor (TFTR) [Fusion Technol. 21, 1324 (1992)]. These activities include preparation of the tritium gas handling system, installation of additional neutron shielding, conversion of the toroidal field coil cooling system from water to a FluorinertTM system, modification of the vacuum system to handle tritium, preparation, and testing of the neutral beam system for tritium operation and a final deuterium–deuterium (D–D) run to simulate expected deuterium–tritium (D–T) operation. Testing of the tritium system with low concentration tritium has successfully begun. Simulation of trace and high power D–T experiments using D–D have been performed. The physics objectives of D–T operation are production of ≊10 MW of fusion power, evaluation of confinement, and heating in deuterium–tritium plasmas, evaluation of α‐particle heating of electrons, and collective effects driven by alpha particles and testing of diag...

Published
1994
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