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135 results on '"Erents, K."'

11. Recent progress in JET on Heating and Current Drive studies in view of ITER

Author

Ongena, J., Mailloux, J., Baranov, Y., Bertalot, L., Callis, C., Corrigan, G., Ekedahl, A., Erents, K., Eriksson, L., Goniche, M., Hellsten, T., Jenkins, I., Johnson, T., Keeling, D., Kiptily, V., Lamalle, P., Laxaback, M., Lerche, E., Mantsinen, M., Mayoral, M., Noterdaeme, J., Parail, V., Petrizilka, V., Popovichev, S., Salmi, A., Santala, M., Spence, J., Sharapov, S., Tuccillo, A., Van Eester, D., and EFDA-JET Contributors

Published
2007

12. ELMy H-modes in JET helium-4 plasmas

Author

McDonald, C., Cordey, J.G., Righi, E., Ryter, F., Saibene, G., Sartori, R., Alper, B., Becoulet, M., Brzozowski, J., Coffey, I., de Baar, M., de Vries, P., Erents, K., Fundamenski, W., Giroud, C., Jenkins, I., Loarte, A., Lomas, P.J., Maddison, G.P., Mailloux, J., Murari, A., Ongena, J., Rapp, J., Pitts, R.A., Stamp, M., Strachan, J., and Suttrop, W.

Subjects
JET, ITER
Abstract

ELMy H-modes in helium-4 plasmas provide valuable information on ELMy H-mode physics as well as a possible early low activation operational phase for next-step tokamaks, such as ITER. With this in mind, a series of helium-4 H-mode experiments were performed on JET with pure helium-4 NBI auxiliary heating (up to 12 MW). A set of ELMy H-mode plasmas were produced, in both the Type I ELM regime and a second regime, which showed characteristics similar to the deuterium Type III regime, but with a reverse ELM frequency dependence on power. Sawteeth were also observed, and had similar behaviour to those seen in deuterium. Compared with deuterium plasmas, Type I ELMy H-mode confinement is seen to be 28 +/- 6% poorer in helium-4 plasmas and the L-H power threshold 42 +/- 10% larger. This is the opposite of the behaviour predicted by experimental isotope mass scalings from hydrogenic plasmas.Comparison with a wider hydrogenic database, enables the effects of isotopic charge and mass to be studied independently.

Published
2004

14. Recent results of LCHD coupling experiments with near gas injection in JET

Author

Granucci G., Ekedahl A., Mailloux J., Erents K., Hron M., Joffrin E., Lomas P.J., Mantsinen M., Noterdaeme J.M., Pericoli-Ridolfini V., Petrzilka V., Rantamaki K.M., Sartori R., Silva C., Tuccillo A.A., McDonald D., and JET-EFDA Contributors

Subjects
___
Abstract

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Published
2003

15. Hot spots generated by lower hybrid waves on JET

Author

Rantamaki K.M., Petrzilka V., Ekedahl A., Erents K., Fuchs V., Goniche M., Granucci G., Karttunen S.J., Mailloux J., Mayoral M.L., Zacek F., and the EFDA-JET Contributors

Subjects
___
Abstract

___

Published
2003

18. Analysis of Plasma Edge Profiles at JET

Author

Beurskens, M., Giovannozzi, E., Gunn, J., Andrew, Y., Brix, M., Chareau, J., Erents, K., Gowers, C., Günther, K., Jachmich, S., Kallenbach, A., Korotkov, A., de la Luna, E., Morgan, P., Prentice, R., Proschek, M., Saibene, G., Suttrop, W., Travere, J., Tribaldos, V., Zerbini, M., and EFDA-JET Work Programme Collaborators

Published
2001

19. The role of RF in the optimised shear scenario on JET

Author

Söldner, F., Alper, B., Baranov, Yu.F, Bickley, A., Bondeson, A., Borba, D., Challis, C.D., Conway, G., Cottrell, G.A., de Benedetti, M., Deliyanakis, N., Ekedal, A., Erents, K., Gormezano, C., Govers, C., Hawkens, N.C., Hender, T.C., Huysmans, G.T.A., Joffrin, E., Jones, T.T.C., Litaudon, X., Liu, D.-H., Lomas, P.J., Maas, A., Mailloux, J., Mantsinen, M., Nave, F., Parail, V.V., Rimini, F., Sarazin, Y., Sips, A.C.C.C., Smeulders, P., Stamp, M.F., Tala, T.J.J., von Helleman, M., Ward, D.J., and Zastrow, K.-D.

Published
1999

20. LH wave coupling over ITER-like distances at JET

Author

Rantamäki, K., Ekedahl, A., Goniche, M., Mailloux, J., Petrzilka, V., Granucci, G., Alper, B., Arnoux, G., Baranov, Y., Delpech, L., Erents, K., Hawkes, N., Hobirk, J., Joffrin, E., Kirov, K., Loarer, T., Nave, F., Nunes, I., Ongena, J., Parail, V., Piccolo, F., Rachlew, Elisabeth, Silva, C., Stamp, M., Zastrow, K. -D, Rantamäki, K., Ekedahl, A., Goniche, M., Mailloux, J., Petrzilka, V., Granucci, G., Alper, B., Arnoux, G., Baranov, Y., Delpech, L., Erents, K., Hawkes, N., Hobirk, J., Joffrin, E., Kirov, K., Loarer, T., Nave, F., Nunes, I., Ongena, J., Parail, V., Piccolo, F., Rachlew, Elisabeth, Silva, C., Stamp, M., and Zastrow, K. -D

Abstract

Good coupling of LH power at plasma-launcher distance of 15 cm has been obtained at JET. Near-gas injection is used to increase the density in front of the grill. The role of LH power in the density increase at constant gas level is demonstrated. For the first time at JET the temperature of the hot spots caused by parasitic absorption of LH power has been measured., QC 20141118

Published
2007
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21. Localized bulk electron heating with ICRF mode conversion in the JET tokamak

Author

Mantsinen, M. J., Mayoral, M. L., Van Eester, D., Alper, B., Barnsley, R., Beaumont, P., Bucalossi, J., Coffey, I., Conroy, S., de Baar, M., de Vries, P., Erents, K., Figueiredo, A., Gondhalekar, A., Gowers, C., Hellsten, Torbjörn A. K., Joffrin, E., Kiptily, V., Lamalle, P. U., Lawson, K., Lyssoivan, A., Mailloux, J., Mantica, P., Meo, F., Milani, F., Monakhov, I., Murari, A., Nguyen, F., Noterdaeme, J. M., Ongena, J., Petrov, Y., Rachlew, Elisabeth, Riccardo, V., Righi, E., Rimini, F., Stamp, M., Tuccillo, A. A., Zastrow, K. D., Zerbini, M., Mantsinen, M. J., Mayoral, M. L., Van Eester, D., Alper, B., Barnsley, R., Beaumont, P., Bucalossi, J., Coffey, I., Conroy, S., de Baar, M., de Vries, P., Erents, K., Figueiredo, A., Gondhalekar, A., Gowers, C., Hellsten, Torbjörn A. K., Joffrin, E., Kiptily, V., Lamalle, P. U., Lawson, K., Lyssoivan, A., Mailloux, J., Mantica, P., Meo, F., Milani, F., Monakhov, I., Murari, A., Nguyen, F., Noterdaeme, J. M., Ongena, J., Petrov, Y., Rachlew, Elisabeth, Riccardo, V., Righi, E., Rimini, F., Stamp, M., Tuccillo, A. A., Zastrow, K. D., and Zerbini, M.

Abstract

Ion cyclotron resonance frequencies (ICRF) mode conversion has been developed for localized on-axis and off-axis bulk electron heating on the JET tokamak. The fast magnetosonic waves launched from the low-field side ICRF antennas are mode-converted to short-wavelength waves on the high-field side of the He-3 ion cyclotron resonance layer in D and He-4 plasmas and subsequently damped on the bulk electrons. The resulting electron power deposition, measured using ICRF power modulation, is narrow with a typical full-width at half-maximum of approximate to30 cm (i.e. about 30% of the minor radius) and the total deposited power to electrons comprises at least up to 80% of the applied ICRF power. The ICRF mode conversion power deposition has been kept constant using He-3 bleed throughout the ICRF phase with a typical duration of 4-6 s, i.e. 15-40 energy confinement times. Using waves propagating in the counter-current direction minimizes competing ion damping in the presence of co-injected deuterium beam ions., QC 20100525

Published
2004
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22. Localized bulk electron heating with ICRF mode conversion in the JET tokamak

Author

Mantsinen, M.J., Mayoral, M.-L., Eester, D. Van, Alper, B., Barnsley, R., Beaumont, P., Bucalossi, J., Coffey, I., Conroy, S., Baar, M. de, Vries, P. de, Erents, K., Figueiredo, A., Bondhalekar, A., Gowers, C., Hellsten, T., Joffrin, E., Kiptily, V., Lamalle, P.U., Lawson, K., Lyssoivan, A., Mailloux, J., Mantica, P., Meo, F., Milani, F., Monakhov, I., Murari, A., Nguyen, F., Noterdaeme, J.-M., Ongena, J., Petrov, Y., Rachlew, E., Riccardo, V., Righi, E., Rimini, F., Stamp, M., Tuccillo, A.A., Zastrow, D.-D., Zerbini, M., Mantsinen, M.J., Mayoral, M.-L., Eester, D. Van, Alper, B., Barnsley, R., Beaumont, P., Bucalossi, J., Coffey, I., Conroy, S., Baar, M. de, Vries, P. de, Erents, K., Figueiredo, A., Bondhalekar, A., Gowers, C., Hellsten, T., Joffrin, E., Kiptily, V., Lamalle, P.U., Lawson, K., Lyssoivan, A., Mailloux, J., Mantica, P., Meo, F., Milani, F., Monakhov, I., Murari, A., Nguyen, F., Noterdaeme, J.-M., Ongena, J., Petrov, Y., Rachlew, E., Riccardo, V., Righi, E., Rimini, F., Stamp, M., Tuccillo, A.A., Zastrow, D.-D., and Zerbini, M.

Abstract

Ion cyclotron resonance frequencies (ICRF) mode conversion has been developed for localized on-axis and off-axis bulk electron heating on the JET tokamak. The fast magnetosonic waves launched from the low-field side ICRF antennas are mode-converted to short-wavelength waves on the high-field side of the He-3 ion cyclotron resonance layer in D and He-4 plasmas and subsequently damped on the bulk electrons. The resulting electron power deposition, measured using ICRF power modulation, is narrow with a typical full-width at half-maximum of approximate to30 cm (i.e. about 30% of the minor radius) and the total deposited power to electrons comprises at least up to 80% of the applied ICRF power. The ICRF mode conversion power deposition has been kept constant using He-3 bleed throughout the ICRF phase with a typical duration of 4-6 s, i.e. 15-40 energy confinement times. Using waves propagating in the counter-current direction minimizes competing ion damping in the presence of co-injected deuterium beam ions.

Published
2004

23. Bright spots generated by lower hybrid waves on JET

Author

Rantamäki, K M, primary, Petržílka, V, additional, Andrew, P, additional, Coffey, I, additional, Ekedahl, A, additional, Erents, K, additional, Fuchs, V, additional, Goniche, M, additional, Granucci, G, additional, Joffrin, E, additional, Karttunen, S J, additional, Lomas, P, additional, Mailloux, J, additional, Mantsinen, M, additional, Mayoral, M-L, additional, McDonald, D C, additional, Noterdaeme, J-M, additional, Parail, V, additional, Tuccillo, A A, additional, Žáček, F, additional, and Workprogramme, Contributors to the EFDA—JET, additional

Published
2005
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26. ELMy H-modes in JET helium-4 plasmas

Author

McDonald, D C, primary, Cordey, J G, additional, Righi, E, additional, Ryter, F, additional, Saibene, G, additional, Sartori, R, additional, Alper, B, additional, Becoulet, M, additional, Brzozowski, J, additional, Coffey, I, additional, Baar, M de, additional, Vries, P de, additional, Erents, K, additional, Fundamenski, W, additional, Giroud, C, additional, Jenkins, I, additional, Loarte, A, additional, Lomas, P J, additional, Maddison, G P, additional, Mailloux, J, additional, Murari, A, additional, Ongena, J, additional, Rapp, J, additional, Pitts, R A, additional, Stamp, M, additional, Strachan, J, additional, Suttrop, W, additional, and Contributors, JET EFDA, additional

Published
2004
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27. Localized bulk electron heating with ICRF mode conversion in the JET tokamak

Author

Mantsinen, M.J, primary, Mayoral, M.-L, additional, Eester, D. Van, additional, Alper, B, additional, Barnsley, R, additional, Beaumont, P, additional, Bucalossi, J, additional, Coffey, I, additional, Conroy, S, additional, Baar, M. de, additional, Vries, P. de, additional, Erents, K, additional, Figueiredo, A, additional, Gondhalekar, A, additional, Gowers, C, additional, Hellsten, T, additional, Joffrin, E, additional, Kiptily, V, additional, Lamalle, P.U, additional, Lawson, K, additional, Lyssoivan, A, additional, Mailloux, J, additional, Mantica, P, additional, Meo, F, additional, Milani, F, additional, Monakhov, I, additional, Murari, A, additional, Nguyen, F, additional, Noterdaeme, J.-M, additional, Ongena, J, additional, Petrov, Yu, additional, Rachlew, E, additional, Riccardo, V, additional, Righi, E, additional, Rimini, F, additional, Stamp, M, additional, Tuccillo, A.A, additional, Zastrow, K.-D, additional, Zerbini, M, additional, and contributors, JET EFDA, additional

Published
2003
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28. JET carbon screening experiments using methane gas puffing and its relation to intrinsic carbon impurities

Author

Strachan, J.D, primary, Fundamenski, W, additional, Charlet, M, additional, Corrigan, G, additional, Erents, K, additional, Gafert, J, additional, Giroud, C, additional, Gowers, C, additional, Hellermann, M. von, additional, Horton, L.D, additional, Matthews, G.F, additional, McCracken, G, additional, Philipps, V, additional, Spence, J, additional, Stamp, M.F, additional, Zastrow, K.-D, additional, and Collaborators, EFDA-JET Work Programme, additional

Published
2003
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31. LH Wave Coupling And ICRF Sheaths At JET.

Author

Kirov, K. K., Baranov, Yu., Colas, L., Ekedahl, A., Erents, K., Goniche, M., Jacquet, P., Mailloux, J., Mayoral, M.-L., Petrzilka, V., and Stamp, M.

Subjects
CYCLOTRONS, IONS, ANTENNAS (Electronics), REFLECTANCE, ELECTRONICS
Abstract

Lower Hybrid (LH) wave coupling deteriorates when the system is pulsed with Ion Cyclotron Range of Frequencies (ICRF) antennas magnetically connected to the launcher. This has been attributed to the density modifications by the RF sheaths. Reflection Coefficients (RCs) dependencies are investigated and shown consistent with the sheath physics. Gas puffing near the launcher has been used to improve the coupling. Results from a statistical analysis of a particular set of data are summarised. [ABSTRACT FROM AUTHOR]

Published
2007
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32. Coupling Of The JET ICRF Antennas In ELMy H-mode Plasmas With ITER Relevant Plasma—Straps Distance.

Author

Mayoral, M.-L., Monakhov, I., Jacquet, P., de Baar, M., Brix, M., Graham, M., Erents, K., Hobirk, J., Korotkov, A., Lomas, P., Mailloux, J., McDonald, D. C., Ongena, J., Stamp, M., and Walden, A.

Subjects
ANTENNAS (Electronics), ASTRONOMICAL perturbation, FLUIDS, PERTURBATION theory, DEUTERIUM
Abstract

In ITER, the requirement for the ICRF antenna is to deliver 20 MW in ELMy H-mode plasmas with an averaged antenna—plasma separatrix distance of 14 cm [1]. Two major problems will have to be solved: the very fast change in antenna loading during ELMs and the decrease of the loading when the plasma is pushed far away from the antenna. JET has the capability to combine these conditions and for the first time, experiments were performed in ELMy H-mode at antenna—separatrix distance, referred as ROG, varied from 10 to 14 cm. When ROG was increased, the perturbation caused by ELMs was found to decrease significantly and the loading between ELMs was found to deteriorate to very low values. In order to compensate the latter unwanted effect, different levels of deuterium gas were injected in the edge either from the divertor, the midplane or the top of the tokamak. Using this technique, the loading was increased by up to a factor 6 and up to 8 MW of ICRF power were coupled. [ABSTRACT FROM AUTHOR]

Published
2007
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35. Long Distance Coupling of Lower Hybrid Waves in ITER Relevant Edge Conditions in JET Reversed Shear Plasmas.

Author

Ekedahl, A., Granucci, G., Mailloux, J., Petrzilka, V., Rantamäki, K., Baranov, Y., Erents, K., Goniche, M., Joffrin, E., Lomas, P.J., Mantsinen, M., McDonald, D., Noterdaeme, J.-M., Pericoli, V., Sartori, R., Silva, C., Stamp, M., Tuccillo, A.A., and Zacek, F.

Subjects
WAVES (Physics), DENSITY currents, ELECTRON distribution, PLASMA gases, REVERSED field pinches
Abstract

A significant step towards demonstrating the feasibility of coupling Lower Hybrid (LH) waves in ITER has been achieved in the latest LH current drive experiments in JET. The local electron density in front of the LH launcher was increased by injecting gas (D2 or CD4) from a dedicated gas injection module magnetically connected to the launcher. PLHCD=3MW was coupled with an average reflection coefficient of 5%, at a distance between the last closed flux surface and the launcher of 10cm, in plasmas with an internal transport barrier (ITB) and H-mode edge, with type I and type III ELMs. Following a modification of the gas injection system, in order to optimise the gas localisation with respect to the LH launcher, injection of D2 proved to be more efficient than CD4. A D2 flux of 5-8×1021el/s provided good coupling conditions at a clearance of 10cm, while when using CD4, a flux of 12×1021el/s was required at 9cm. The plasma performance (neutron rate, H-factor, ion temperature) was similar with D2 and CD4. An additional advantage with D2 injection was found, as it reduced the amplitude of the ELMs, which further facilitated the LH coupling. Furthermore, preliminary results of the study of the behaviour of electron density profile in the scrape-off layer during injection of C2H6 and C3H8 are reported. Finally, the appearance of hot spots, resulting from parasitic absorption of LHCD power in front of the launcher mouth, was studied in the long distance discharges with near gas injection. © 2003 American Institute of Physics [ABSTRACT FROM AUTHOR]

Published
2003
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36. LHCD coupling during H-mode and ITB in JET plasmas.

Author

Ridolfini, V. Pericoli, Podda, S., Mailloux, J., Sarazin, Y., Baranov, Y., Bernabei, S., Cesario, R., Cocilovo, V., Ekedahl, A., Erents, K., Granucci, G., Imbeaux, F., Leuterer, F., Mirizzi, F., Matthews, G., Panaccione, L., Rimini, F., and Tuccillo, A. A.

Subjects
PLASMA gases, IONIZATION (Atomic physics)
Abstract

Good coupling of the LH power during the whole internal transport barrier (ITB) phase has been achieved in JET by fitting the plasma shape to the LH antenna shape and by injecting CD[sub 4] gas from a pipe near to the LH grill. No adverse effect on the edge pedestal or on the ITB quality, or significant impurity influx is observed. The key is the low ionization potential of all the CD[sub 4] dissociation chain, which is completed inside the SOL. Promising perspectives are open for injecting safely LHCD with more power during an ITB. [ABSTRACT FROM AUTHOR]

Published
2001

37. Isotope identity experiments in JET

Author

Cordey, J G, primary, Alper, B, additional, Budny, R, additional, Christiansen, J P, additional, Coffey, I, additional, Erents, K, additional, Harbour, P, additional, Horton, L D, additional, Lawson, K, additional, Matthews, G F, additional, Saibene, G, additional, Sartori, R, additional, Strachan, J, additional, and Thomsen, K, additional

Published
2000
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38. Characterization of the frequency ranges of the plasma edge fluctuation spectra

Author

Carreras, B. A., primary, Balbin, R., additional, van Milligen, B., additional, Pedrosa, M. A., additional, Garcia-Cortes, I., additional, Sanchez, E., additional, Hidalgo, C., additional, Bleuel, J., additional, Endler, M., additional, Thomsen, H., additional, Chankin, A., additional, Davies, S., additional, Erents, K., additional, and Matthews, G. F., additional

Published
1999
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39. The role of RF in the optimized shear scenario on JET

Author

Söldner, F. X., primary, Alper, B., additional, Baranov, Yu. F., additional, Bickley, A., additional, Bondeson, A., additional, Borba, D., additional, Challis, C. D., additional, Conway, G., additional, Cottrell, G. A., additional, de Benedetti, M., additional, Deliyanakis, N., additional, Ekedahl, A., additional, Erents, K., additional, Gormezano, C., additional, Gowers, C., additional, Hawkes, N. C., additional, Hender, T. C., additional, Huysmans, G. T. A., additional, Joffrin, E., additional, Jones, T. T. C., additional, Litaudon, X., additional, Liu, D.-H., additional, Lomas, P. J., additional, Maas, A., additional, Mailloux, J., additional, Mantsinen, M., additional, Nave, F., additional, Parail, V. V., additional, Rimini, F., additional, Sarazin, Y., additional, Sips, A. C. C., additional, Smeulders, P., additional, Stamp, M. F., additional, Tala, T. J. J., additional, von Hellermann, M., additional, Ward, D. J., additional, and Zastrow, K.-D., additional

Published
1999
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41. Review of vacuum vessel conditioning procedures at JET and their impact on plasma operation

Author

Saibene, G., primary, Rossi, A., additional, Monk, R.D., additional, Orchard, J., additional, Andrew, P., additional, Barnsley, R., additional, Cushing, D., additional, Coad, P.J., additional, Davies, S., additional, Erents, K., additional, Guo, H.Y., additional, Lawson, K., additional, Lingertat, J., additional, Matthews, G., additional, Sips, G., additional, Stamp, M., additional, and Tanga, A., additional

Published
1995
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43. The role of RF in the optimized shear scenario on JET.

Author

Söldner, F. X., Alper, B., Baranov, Yu. F., Bickley, A., Bondeson, A., Borba, D., Challis, C. D., Conway, G., Cottrell, G. A., de Benedetti, M., Deliyanakis, N., Ekedahl, A., Erents, K., Gormezano, C., Gowers, C., Hawkes, N. C., Hender, T. C., Huysmans, G. T. A., Joffrin, E., and Jones, T. T. C.

Published
1999
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46. Progress in internal transport barrier plasmas with lower hybrid current drive and heating in JET (Joint European Torus).

Author

Mailloux, J., Alper, B., Baranov, Y., Becoulet, A., Cardinali, A., Castaldo, C., Cesario, R., Conway, G., Challis, C. D., Crisanti, F., de Baar, M., de Vries, P., Ekedahl, A., Erents, K., Gowers, C., Hawkes, N. C., Hogeweij, G. M. D., Imbeaux, F., Joffrin, E., and Litaudon, X.

Subjects
INTERNAL waves, PLASMA astrophysics
Abstract

In optimized shear plasmas in the Joint European Torus [P. H. Rebut and B. E. Keen, Fusion Technol. 11, 13 (1987)], safety factor (q) profiles with negative magnetic shear are produced by applying lower hybrid (LH) waves during the plasma current ramp-up phase. These plasmas produce a barrier to the electron energy transport. The radius at which the barrier is located increases with the LH wave power. When heated with high power from ion cyclotron resonance heating and neutral beam injection, they can additionally produce transient internal transport barriers (ITBs) seen on the ion temperature, electron density, and toroidal rotation velocity profiles. Due to recent improvements in coupling, q profile control with LH current drive in ITB plasmas with strong combined heating can be explored. These new experiments have led to ITBs sustained for several seconds by the LH wave. Simulations show that the current driven by the LH waves peaks at the ITB location, indicating that it can act in the region of low magnetic shear. © 2002 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Published
2002

47. Edge localized modes and fluctuations in the JET SOL region

Author

Gonçalves, B BG, Hidalgo, C CH, Pedrosa, M MAP, Silva, C CS, Balbín, R RB, Erents, K KE, Hron, M MH, Loarte, A AL, and Matthews, G GM

Abstract

The statistical properties of the radial propagation of edge localized modes (ELMs) have been investigated in the Scrape-off layer (SOL) region of the JET tokamak. ELM events propagate radially with effective radial velocities in the range of 1000 m s−1. Experimental results show a link between the radial velocity and the size of transport events. This suggests the importance of the competition between both parallel and radial transport to explain particle losses onto the divertor plates. Parallel flows show a transient increase during the appearance of ELMs, providing evidence of a coupling between parallel dynamics and radial transport.

Published
2003

48. Velocity fluctuations and time dependent E×B flows in the JET boundary region.

Author

Gonçalves, B., Hidalgo, C., Pedrosa, M. A., Silva, C., Erents, K., and Mathews, G.

Subjects
PLASMA gases, SCIENTIFIC apparatus & instruments
Abstract

Fluctuations in the phase velocity of fluctuations have been computed from floating potential fluctuations in the JET plasma boundary region. Experimental results reinforce the idea that, in some conditions, fluctuations in the phase velocity are linked with fluctuations in radial-poloidal electric fields opening the possibility to investigate turbulent transport in the plasma core region from measurements of density fluctuations. These results indicate that time dependent radial electric fields and E × B shearing rates might be computed in the plasma core from measurement of density fluctuations. [ABSTRACT FROM AUTHOR]

Published
2003

49. Particle balance and wall pumping in tokamaks

Author

Gohen, S A, Ehrenberg, J, Jones, T T C, Gondhalekar, A, Bures, M, Coad, P, Kock, L de, Erents, K, Barbour, P, Morgan, P D, O'Rourke, J, Tagle, J A, Watkins, M, and Team, The JET

Published
1987

50. Trapping and re-emission of fast deuterium ions from nickel II

Author

Erents, K. and McCracken, G. M.

Abstract

Experiments on deuterium bombardment of nickel have been continued and measurements of gas release during and after bombardment have been compared. The results are consistent with the hypothesis that gas release from the solid is controlled by radiation damage sites produced by the incident ions slowing down in the metal. The population of these damage sites as a function of incident ion dose has been deduced.

Published
1970
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