Search Results - "Laqua, H."

First Observation of a Stable Highly Dissipative Divertor Plasma Regime on the Wendelstein 7-X Stellarator by Zhang, D, König, R, Feng, Y, Burhenn, R, Brezinsek, S, Jakubowski, M, Buttenschön, B, Niemann, H, Pavone, A, Krychowiak, M, Kwak, S, Svensson, J, Gao, Y, Pedersen, T S, Alonso, A, Baldzuhn, J, Beidler, C D, Biedermann, C, Bozhenkov, S, Brunner, K J, Damm, H, Hirsch, M, Giannone, L, Drewelow, P, Effenberg, F, Fuchert, G, Hammond, K C, Höfel, U, Killer, C, Knauer, J, Laqua, H P, Laube, R, Pablant, N, Pasch, E, Penzel, F, Rahbarnia, K, Reimold, F, Thomsen, H, Winters, V, Wagner, F, Klinger, T, W-X Team

“…For the first time, the optimized stellarator Wendelstein 7-X has operated with an island divertor. An operation regime in hydrogen was found in which the…”
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Operational Characteristics of the 175-GHz Continuous-Wave Clinotron by Ponomarenko, S., Braune, H., Khutoryan, E., Kishko, S., Kovshov, Y., Kuleshov, A., Laqua, H. P., Moseev, D., Stange, T., Vlasenko, S.

“…The operational characteristics of a watt-level water-cooled 175-GHz continuous-wave (CW) clinotron are studied experimentally and discussed in this article…”
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Impact of Magnetic Field Configuration on Heat Transport in Stellarators and Heliotrons by Warmer, Felix, Tanaka, K, Xanthopoulos, P, Nunami, M, Nakata, M, Beidler, C D, Bozhenkov, S A, Beurskens, M N A, Brunner, K J, Ford, O P, Fuchert, G, Funaba, H, Geiger, J, Gradic, D, Ida, K, Igami, H, Kubo, S, Langenberg, A, Laqua, H P, Lazerson, S, Morisaki, T, Osakabe, M, Pablant, N, Pasch, E, Peterson, B, Satake, S, Seki, R, Shimozuma, T, Smith, H M, Stange, T, Stechow, A V, Sugama, H, Suzuki, Y, Takahashi, H, Tokuzawa, T, Tsujimura, T, Turkin, Y, Wolf, R C, Yamada, I, Yanai, R, Yasuhara, R, Yokoyama, M, Yoshimura, Y, Yoshinuma, M, Zhang, D, W-X Team, Lhd Experimental Group

“…We assess the magnetic field configuration in modern fusion devices by comparing experiments with the same heating power, between a stellarator and a…”
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Influence of sawtooth oscillations on fast ions in a stellarator by Moseev, D., Zanini, M., Kasahara, H., Laqua, H.P., Funaba, H., Hayashi, W.H.J., Heidbrink, W., Ida, K., Igami, H., Kawamoto, Y., Kenmochi, N., Lazerson, S.A., Nishiura, M., Ochoukov, R., Ogawa, K., Rud, M., Salewski, M., Seki, T., Tamura, N., Tanaka, K., Tokuzawa, T., Yoshinuma, M.

“…Abstract Sawtooth oscillations in tokamaks frequently lead to the redistribution of energetic ions, mainly on passing orbits, causing their expulsion from the…”
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The Trigger-Time-Event System for Wendelstein 7-X: Overview and First Operational Experiences by Schacht, J., Laqua, H., Muller, I., Puttnies, H., Skodzik, J.

“…The superconducting stellarator Wendelstein 7-X (W7-X) started plasma operation in December 2015 after the commissioning phase of the machine. The main…”
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Turbulence-reduced high-performance scenarios in Wendelstein 7-X by Ford, O.P., Beurskens, M., Bozhenkov, S.A., Lazerson, S., Vanó, L., Alonso, A., Baldzuhn, J., Beidler, C.D., Biedermann, C., Burhenn, R., Fuchert, G., Hartmann, D., Hirsch, M., Langenberg, A., Laqua, H., McNeely, P., Pablant, N., Pasch, E., Reimold, F., Romba, T., Rust, N., Schroeder, R., Scott, E.R., Stange, T., Smith, H.M., Gradic, D., Wolf, R.C., Zhang, D.

“…Abstract In the Wendelstein 7-X (W7-X) stellarator, turbulence is the dominant transport mechanism in most discharges. This leads to a ‘clamping’ of ion…”
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ICRF plasma production at hydrogen minority regime in LHD by Kovtun, Yu.V., Kasahara, H., Moiseenko, V.E., Kamio, S., Seki, T., Saito, K., Seki, R., Dinklage, A., Hartmann, D., Laqua, H., Stange, T., Lazerson, S., Alonso, A., Wauters, T., Kazakov, Ye, Ongena, J., Garkusha, I.E.

“…Abstract This study aim is to develop further an ion cyclotron range of frequencies (ICRF) method of plasma production in stellarators based on the minority…”
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Stray radiation energy fluxes in ITER based on a multiresonator model by Moseev, D., Oosterbeek, J.W., Sirinelli, A., Corre, Y., Houry, M., Korsholm, S.B., Laqua, H.P., Marsen, S., Preynas, M., Rasmussen, J., Salewski, M., Stange, T., Udintsev, V.

“…•Accounting for spatial distribution of the stray radiation energy flux, including ports and cryopumps during start-up in the first plasma operation and…”
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Resonant and Nonresonant Electron Cyclotron Heating at Densities above the Plasma Cutoff by O-X-B Mode Conversion at the W7-As Stellarator by Laqua, H. P., Erckmann, V., Hartfuß, H. J., Laqua, H.

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Wendelstein 7-X Program-Demonstration of a Stellarator Option for Fusion Energy by Wolf, R. C., Beidler, C. D., Dinklage, A., Helander, P., Laqua, H. P., Schauer, F., Sunn Pedersen, T., Warmer, F.

“…The superconducting stellarator Wendelstein 7-X is currently being commissioned. First plasmas are expected for the second half of 2015. W7-X is designed to…”
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Preparation of W7-X CoDaC for OP2 by Winter, A., Bluhm, T., Bosch, H.-S., Brandt, K., Dumke, S., Grahl, M., Grun, M., Holtz, A., Laqua, H., Lewerentz, M., Makowski, D., Pingel, S., Riemann, H., Schacht, J., Schaumann, K., Spring, A., Valet, S.

“…The superconducting stellarator Wendelstein 7-X has successfully concluded its third operation phase in October 2018. The machine will see substantial changes…”
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Wendelstein 7-X on the path to long-pulse high-performance operation by Endler, M., Baldzuhn, J., Beidler, C.D., Bosch, H.-S., Bozhenkov, S., Buttenschön, B., Dinklage, A., Fellinger, J., Feng, Y., Fuchert, G., Gao, Y., Geiger, J., Grulke, O., Hartmann, D., Jakubowski, M., König, R., Laqua, H.P., Lazerson, S., McNeely, P., Naujoks, D., Neuner, U., Otte, M., Pasch, E., Sunn Pedersen, T., Perseo, V., Puig Sitjes, A., Rahbarnia, K., Rust, N., Schmitz, O., Spring, A., Stange, T., von Stechow, A., Turkin, Y., Wang, E., Wolf, R.C.

“…•W7-X achieved several of its project goals during the first operation phases.•Boronisation reduced the impurity content strongly and allowed high-density…”
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W7-X logbook REST API for processing experimental metadata and data enrichment at the Wendelstein 7-X stellarator by Grahl, M., Spring, A., Andreeva, T., Bluhm, T., Bozhenkov, S., Dumke, S., Geiger, J., Grulke, O., Grün, M., Holtz, A., Höfel, U., Laqua, H., Lewerentz, M., Riemann, H., Schilling, J., von Stechow, A., Svensson, J., Winter, A.

“…Contextual metadata becomes an important factor for the work with research data, which is created in large amounts at fusion experiments. In its first…”
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The new W7-X logbook – A software for effective experiment documentation and collaborative research at Wendelstein 7-X by Grahl, M., Spring, A., Bluhm, T., Bosch, H.-S., Brakel, R., Dumke, S., van Eeten, P., Grün, M., Hirsch, M., Holtz, A., Laqua, H., Lewerentz, M., Riemann, H., Werner, A.

“…•Central web logbook for device operation and experimentation at W7-X.•Automatically extracted metadata from W7-X control system.•Includes information from all…”
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Plasma Production in ICRF in the Uragan-2M Stellarator in Hydrogen–Helium Gas Mixture by Moiseenko, V. E., Kovtun, Yu. V., Lozin, A. V., Pavlichenko, R. O., Shapoval, A. N., Grigor’eva, L. I., Kozulya, M. M., Maznichenko, S. M., Korovin, V. B., Kramskoy, E. D., Zamanov, N. V., Siusko, Y. V., Baron, D. I., Krasiuk, A. Yu, Romanov, V. S., Garkusha, I. E., Wauters, T., Alonso, A., Brakel, R., Dinklage, A., Hartmann, D., Kazakov, Ye, Laqua, H., Ongena, J., Stange, T.

“…Plasma production experiments in helium at Uragan-2M have been performed to investigate the role of the hydrogen minority in helium. The experiments presented…”
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Archive WEB API: A web service for the experiment data archive of Wendelstein 7-X by Grahl, M., Bluhm, T., Grün, M., Hennig, C., Holtz, A., Krom, J.G., Kühner, G., Laqua, H., Lewerentz, M., Riemann, H., Spring, A., Werner, A.

“…•Concept and first user experience of the Archive Web API.•RESTful web service provides read and write access to the experiment data archive of W7-X.•Supports…”
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The ECRH-Power Upgrade at the Wendelstein 7-X Stellarator by Laqua, H. P., Avramidis, K. A., Braune, H., Chelis, I., Gantenbein, G., Illy, S., Ioannidis, Z., Jelonnek, J., Jin, J., Krier, L., Lechte, C., Leggieri, A., Legrand, F., Marsen, S., Moseev, D., Oosterbeek, H., Rzesnicki, T., Ruess, T., Stange, T., Thumm, M., Tigelis, I., Wolf, R. C.

“…The existing ECRH system at W7-X consists of 10 gyrotrons, with output power levels ranging from 0.6 MW up to 1.0 MW each at a frequency of 140 GHz,…”
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Secondary paracentral retinal holes following internal limiting membrane removal by Steven, P, Laqua, H, Wong, D, Hoerauf, H

“…Aim: To report on a new postoperative finding after delamination of the internal limiting membrane (ILM) for the treatment of different macular pathologies…”
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Compression of time-vectors in W7-X archived measurements by Krom, J.G., Daher, R., Bluhm, T., Dumke, S., Grahl, M., Grün, M., Hennig, C., Holtz, A., Laqua, H., Lewerentz, M., Riemann, H., Spring, A., Werner, A.

“…Wendelstein 7-X is, as a stellerator, in principle capable of very long operation. The Control and Data-acquisition (codac) systems around w7x have, therefore,…”
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New advanced operational regime on the W7-AS stellarator by McCormick, K, Grigull, P, Burhenn, R, Brakel, R, Ehmler, H, Feng, Y, Gadelmeier, F, Giannone, L, Hildebrandt, D, Hirsch, M, Jaenicke, R, Kisslinger, J, Klinger, T, Klose, S, Knauer, J P, König, R, Kühner, G, Laqua, H P, Naujoks, D, Niedermeyer, H, Pasch, E, Ramasubramanian, N, Rust, N, Sardei, F, Wagner, F, Weller, A, Wenzel, U, Werner, A

“…A promising new plasma operational regime on the Wendelstein stellarator W7-AS has been discovered. It is extant above a threshold density and characterized by…”
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