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1. Changeover between helium and hydrogen fueled plasmas in JET and WEST

Author: T. Wauters, R. Bisson, E. Delabie, D. Douai, A. Gallo, J. Gaspar, I. Jepu, Y. Kovtun, E. Pawelec, D. Matveev, A. Meigs, S. Brezinsek, I. Coffey, T. Dittmar, N. Fedorczak, J. Gunn, A. Hakola, P. Jacquet, K. Kirov, E. Lerche, J. Likonen, E. Litherland-Smith, T. Loarer, P. Lomas, C. Lowry, M. Maslov, I. Monakhov, J. Morales, C. Noble, R. Nouailletas, B. Pégourié, C. Perez von Thun, R.A. Pitts, C. Reux, F. Rimini, H. Sheikh, S. Silburn, H. Sun, D. Taylor, E. Tsitrone, S. Vartanian, E. Wang, and A. Widdowson
Subjects: JET, WEST, Changeover, Helium, Hydrogen, ICWC, Nuclear engineering. Atomic power, TK9001-9401
Abstract: The pre-fusion power operation (PFPO) phase of ITER, as described in the ITER research plan with Staged Approach,22 ITER Organization, “ITER Research Plan within the Staged Approach,” ITR-18–003, Aug. 2018. includes both hydrogen (H) and helium (He) plasma operations. In preparation for PFPO, both WEST and JET ran He plasma campaigns to study plasma-wall interactions in a tungsten environment. The campaigns included a back-and-forth transition between H or deuterium (D) and He plasma operation allowing the assessment of the achievable plasma content as well as the accessible wall reservoirs for respective species. The WEST changeovers included tokamak pulses with a fixed divertor configuration. The JET changeovers applied ion cyclotron wall conditioning (ICWC) and tokamak pulses including limiter phases and four different divertor configurations. Glow discharge conditioning (GDC) was applied to complete the changeovers. The results are characterized by subdivertor optical and mass spectrometric gas analyzers and spatially resolved optical emission spectroscopy. A He content of 96–97 % after H operations is achieved by tens of ICWC pulses (JET) and several dedicated diverted plasmas (WEST and JET), while a fivefold is estimated to be required for the back transition. Effective pumping of the wall released species is a key parameter for a fast changeover. Upon applying higher heating power, the relative content of the fueled plasma species decreases. The JET gas balance analysis indicates that He operation may increase H retention. WEST divertor spectroscopy indicates a larger He inventory near the inner divertor strike line. He GDC has a clear effect on the He recycling light at the WEST divertor while D GDC did not reduce the long lasting He content observed in D pulses after the JET He campaign.
Published: 2024
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2. Comparison of ion cyclotron wall conditioning discharges in hydrogen and helium in JET

Author: Y. Kovtun, T. Wauters, D. Matveev, R. Bisson, I. Jepu, S. Brezinsek, I. Coffey, E. Delabie, A. Boboc, T. Dittmar, A. Hakola, P. Jacquet, K. Kirov, E. Lerche, J. Likonen, E. Litherland-Smith, T. Loarer, P. Lomas, C. Lowry, E. Pawelec, C. Perez von Thun, A. Meigs, M. Maslov, I. Monakhov, C. Noble, S. Silburn, H. Sun, D. Taylor, E. Tsitrone, A. Widdowson, H. Sheikh, and D. Douai
Subjects: Wall conditioning, Radio-frequency discharge, Tokamak, Plasma production, Ion cyclotron, Nuclear engineering. Atomic power, TK9001-9401
Abstract: This paper explores the plasma parameters of helium and hydrogen Ion Cyclotron Wall Conditioning (ICWC) discharges performed in JET as part of a He/H fuelling changeover experiment. The conducted study shows that plasma with a higher density is formed in helium than in hydrogen. A distinct glow in the ion cyclotron resonance zone is observed throughout the discharge in He. In H-ICWC discharges, a lower radio-frequency coupling efficiency and coupled power was observed than in He-ICWC discharges. While the helium concentration decreased with the number of H-ICWC pulses and the same for hydrogen in He-ICWC, which is the intended result of the plasma wall interaction in the ICWC changeover procedure, the main features of hydrogen as well as the helium IC discharge do not change dramatically.
Published: 2023
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3. A systematic investigation of radiation collapse for disruption avoidance and prevention on JET tokamak

Author: R. Rossi, M. Gelfusa, T. Craciunescu, L. Spolladore, I. Wyss, E. Peluso, J. Vega, C. F. Maggi, J. Mailloux, M. Maslov, A. Murari, and on behalf of JET Contributors
Subjects: Nuclear and particle physics. Atomic energy. Radioactivity, QC770-798
Abstract: To produce fusion reactions efficiently, thermonuclear plasmas have to reach extremely high temperatures, which is incompatible with their coming into contact with material surfaces. Confinement of plasmas using magnetic fields has progressed significantly in the last years, particularly in the tokamak configuration. Unfortunately, all tokamak devices, and particularly metallic ones, are plagued by catastrophic events called disruptions. Many disruptions are preceded by anomalies in the radiation patterns, particularly in ITER-relevant scenarios. These specific forms of radiation emission either directly cause or reveal the approaching collapse of the configuration. Detecting the localization of these radiation anomalies in real time requires an innovative and specific elaboration of bolometric measurements, confirmed by visible cameras and the inversion of sophisticated tomographic algorithms. The information derived from these measurements can be interpreted in terms of local power balances, which suggest a new quantity, the radiated power divided by the plasma internal energy, to determine the criticality of the plasma state. Combined with robust indicators of the temperature profile shape, the identified anomalous radiation patterns allow determination of the sequence of macroscopic events leading to disruptions. A systematic analysis of JET campaigns at high power in deuterium, full tritium, and DT, for a total of almost 2000 discharges, proves the effectiveness of the approach. The warning times are such that, depending on the radiation anomaly and the available actuators, the control system of future devices is expected to provide enough notice to enable deployment of effective prevention and avoidance strategies.
Published: 2023
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4. Fast-ion orbit origin of neutron emission spectroscopy measurements in the JET DT campaign

Author: H. Järleblad, L. Stagner, J. Eriksson, M. Nocente, K. Kirov, M. Rud, B.S. Schmidt, M. Maslov, D. King, D. Keeling, C. Maggi, J. Garcia, E.A. Lerche, P. Mantica, Y. Dong, M. Salewski, and JET Contributors
Subjects: fast ion, orbit, diagnostics, dt, neutron emission spectroscopy, sensitivity, Nuclear and particle physics. Atomic energy. Radioactivity, QC770-798
Abstract: In the JET DTE2 deuterium-tritium campaign, neutron diagnostics were employed to measure 14 MeV neutrons originating from D(T,n) ^4 He reactions. In discharge 99965, a diamond matrix detector (KM14) and a magnetic proton recoil (MPRu) detector with a vertical and an oblique line-of-sight were used, respectively. At the timepoints of interest, a significant decrease in the expected diagnostic signals can be observed as electromagnetic wave heating in the ion cyclotron range of frequencies (ICRF) is switched off. Utilizing only TRANSP simulation data, the fast-ion distribution is found to have been likely composed mostly of trapped orbits. In contrast, analysis performed using orbit weight functions revealed that the majority of neutrons in the KM14 $E_{d} = 9.3$ MeV and MPRu $X_\textrm{cm} = 33$ cm measurement bins are to have originated from fast deuterium ions on co-passing orbits. This work explains the perhaps surprising results and shows that the relative signal decrease as ICRF heating is switched off is largest for counter-passing orbits. Finally, for the magnetic equilibria of interest, it is shown how stagnation orbits, corresponding to ${\sim} 1$ % of the fast-ion distribution, were completely unobservable by the KM14 diagnostic.
Published: 2024
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5. Overview of the EUROfusion Tokamak Exploitation programme in support of ITER and DEMO

Author: E. Joffrin, M. Wischmeier, M. Baruzzo, A. Hakola, A. Kappatou, D. Keeling, B. Labit, E. Tsitrone, N. Vianello, the ASDEX Upgrade Team, JET Contributors, the MAST-U Team, the TCV Team, the WEST Team, the EUROfusion Tokamak Exploitation Team:, D. Abate, J. Adamek, M. Agostini, C. Albert, F.C.P. Albert Devasagayam, S. Aleiferis, E. Alessi, J. Alhage, S. Allan, J. Allcock, M. Alonzo, G. Anastasiou, E. Andersson Sunden, C. Angioni, Y. Anquetin, L. Appel, G.M. Apruzzese, M. Ariola, C. Arnas, J.F. Artaud, W. Arter, O. Asztalos, L. Aucone, M.H. Aumeunier, F. Auriemma, J. Ayllon, E. Aymerich, A. Baciero, F. Bagnato, L. Bähner, F. Bairaktaris, P. Balázs, L. Balbinot, I. Balboa, M. Balden, A. Balestri, M. Baquero Ruiz, T. Barberis, C. Barcellona, O. Bardsley, S. Benkadda, T. Bensadon, E. Bernard, M. Bernert, H. Betar, R. Bianchetti Morales, J. Bielecki, R. Bilato, P. Bilkova, W. Bin, G. Birkenmeier, R. Bisson, P. Blanchard, A. Bleasdale, V. Bobkov, A. Boboc, A. Bock, K. Bogar, P. Bohm, T. Bolzonella, F. Bombarda, N. Bonanomi, L. Boncagni, D. Bonfiglio, R. Bonifetto, M. Bonotto, D. Borodin, I. Borodkina, T.O.S.J. Bosman, C. Bourdelle, C. Bowman, S. Brezinsek, D. Brida, F. Brochard, R. Brunet, D. Brunetti, V. Bruno, R. Buchholz, J. Buermans, H. Bufferand, P. Buratti, A. Burckhart, J. Cai, R. Calado, J. Caloud, S. Cancelli, F. Cani, B. Cannas, M. Cappelli, S. Carcangiu, A. Cardinali, S. Carli, D. Carnevale, M. Carole, M. Carpita, D. Carralero, F. Caruggi, I.S. Carvalho, I. Casiraghi, A. Casolari, F.J. Casson, C. Castaldo, A. Cathey, F. Causa, J. Cavalier, M. Cavedon, J. Cazabonne, M. Cecconello, L. Ceelen, A. Celora, J. Cerovsky, C.D. Challis, R. Chandra, A. Chankin, B. Chapman, H. Chen, M. Chernyshova, A.G. Chiariello, P. Chmielewski, A. Chomiczewska, C. Cianfarani, G. Ciraolo, J. Citrin, F. Clairet, S. Coda, R. Coelho, J.W. Coenen, I.H. Coffey, C. Colandrea, L. Colas, S. Conroy, C. Contre, N.J. Conway, L. Cordaro, Y. Corre, D. Costa, S. Costea, D. Coster, X. Courtois, C. Cowley, T. Craciunescu, G. Croci, A.M. Croitoru, K. Crombe, D.J. Cruz Zabala, G. Cseh, T. Czarski, A. Da Ros, A. Dal Molin, M. Dalla Rosa, Y. Damizia, O. D’Arcangelo, P. David, M. De Angeli, E. De la Cal, E. De La Luna, G. De Tommasi, J. Decker, R. Dejarnac, D. Del Sarto, G. Derks, C. Desgranges, P. Devynck, S. Di Genova, L.E. di Grazia, A. Di Siena, M. Dicorato, M. Diez, M. Dimitrova, T. Dittmar, L. Dittrich, J.J. Domínguez Palacios Durán, P. Donnel, D. Douai, S. Dowson, S. Doyle, M. Dreval, P. Drews, L. Dubus, R. Dumont, D. Dunai, M. Dunne, A. Durif, F. Durodie, G. Durr Legoupil Nicoud, B. Duval, R. Dux, T. Eich, A. Ekedahl, S. Elmore, G. Ericsson, J. Eriksson, B. Eriksson, F. Eriksson, S. Ertmer, A. Escarguel, B. Esposito, T. Estrada, E. Fable, M. Faitsch, N. Fakhrayi Mofrad, A. Fanni, T. Farley, M. Farník, N. Fedorczak, F. Felici, X. Feng, J. Ferreira, D. Ferreira, N. Ferron, O. Fevrier, O. Ficker, A.R. Field, A. Figueiredo, N. Fil, D. Fiorucci, M. Firdaouss, R. Fischer, M. Fitzgerald, M. Flebbe, M. Fontana, J. Fontdecaba Climent, A. Frank, E. Fransson, L. Frassinetti, D. Frigione, S. Futatani, R. Futtersack, S. Gabriellini, D. Gadariya, D. Galassi, K. Galazka, J. Galdon, S. Galeani, D. Gallart, A. Gallo, C. Galperti, M. Gambrioli, S. Garavaglia, J. Garcia, M. Garcia Munoz, J. Gardarein, L. Garzotti, J. Gaspar, R. Gatto, P. Gaudio, M. Gelfusa, J. Gerardin, S.N. Gerasimov, R. Gerru Miguelanez, G. Gervasini, Z. Ghani, F.M. Ghezzi, G. Ghillardi, L. Giannone, S. Gibson, L. Gil, A. Gillgren, E. Giovannozzi, C. Giroud, G. Giruzzi, T. Gleiter, M. Gobbin, V. Goloborodko, A. González Ganzábal, T. Goodman, V. Gopakumar, G. Gorini, T. Görler, S. Gorno, G. Granucci, D. Greenhouse, G. Grenfell, M. Griener, W. Gromelski, M. Groth, O. Grover, M. Gruca, A. Gude, C. Guillemaut, R. Guirlet, J. Gunn, T. Gyergyek, L. Hagg, J. Hall, C.J. Ham, M. Hamed, T. Happel, G. Harrer, J. Harrison, D. Harting, N.C. Hawkes, P. Heinrich, S. Henderson, P. Hennequin, R. Henriques, S. Heuraux, J. Hidalgo Salaverri, J. Hillairet, J.C. Hillesheim, A. Hjalmarsson, A. Ho, J. Hobirk, E. Hodille, M. Hölzl, M. Hoppe, J. Horacek, N. Horsten, L. Horvath, M. Houry, K. Hromasova, J. Huang, Z. Huang, A. Huber, E. Huett, P. Huynh, A. Iantchenko, M. Imrisek, P. Innocente, C. Ionita Schrittwieser, H. Isliker, P. Ivanova, I. Ivanova Stanik, M. Jablczynska, S. Jachmich, A.S. Jacobsen, P. Jacquet, A. Jansen van Vuuren, A. Jardin, H. Järleblad, A. Järvinen, F. Jaulmes, T. Jensen, I. Jepu, S. Jessica, T. Johnson, A. Juven, J. Kalis, J. Karhunen, R. Karimov, A.N. Karpushov, S. Kasilov, Y. Kazakov, P.V. Kazantzidis, W. Kernbichler, HT. Kim, D.B. King, V.G. Kiptily, A. Kirjasuo, K.K. Kirov, A. Kirschner, A. Kit, T. Kiviniemi, F. Kjær, E. Klinkby, A. Knieps, U. Knoche, M. Kochan, F. Köchl, G. Kocsis, J.T.W. Koenders, L. Kogan, Y. Kolesnichenko, Y. Kominis, M. Komm, M. Kong, B. Kool, S.B. Korsholm, D. Kos, M. Koubiti, J. Kovacic, Y. Kovtun, E. Kowalska Strzeciwilk, K. Koziol, M. Kozulia, A. Krämer Flecken, A. Kreter, K. Krieger, U. Kruezi, O. Krutkin, O. Kudlacek, U. Kumar, H. Kumpulainen, M.H. Kushoro, R. Kwiatkowski, M. La Matina, M. Lacquaniti, L. Laguardia, P. Lainer, P. Lang, M. Larsen, E. Laszynska, K.D. Lawson, A. Lazaros, E. Lazzaro, M.Y.K. Lee, S. Leerink, M. Lehnen, M. Lennholm, E. Lerche, Y. Liang, A. Lier, J. Likonen, O. Linder, B. Lipschultz, A. Listopad, X. Litaudon, E. Litherland Smith, D. Liuzza, T. Loarer, P.J. Lomas, J. Lombardo, N. Lonigro, R. Lorenzini, C. Lowry, T. Luda di Cortemiglia, A. Ludvig Osipov, T. Lunt, V. Lutsenko, E. Macusova, R. Mäenpää, P. Maget, C.F. Maggi, J. Mailloux, S. Makarov, K. Malinowski, P. Manas, A. Mancini, D. Mancini, P. Mantica, M. Mantsinen, J. Manyer, M. Maraschek, G. Marceca, G. Marcer, C. Marchetto, S. Marchioni, A. Mariani, M. Marin, M. Markl, T. Markovic, D. Marocco, S. Marsden, L. Martellucci, P. Martin, C. Martin, F. Martinelli, L. Martinelli, J.R. Martin Solis, R. Martone, M. Maslov, R. Masocco, M. Mattei, G.F. Matthews, D. Matveev, E. Matveeva, M.L. Mayoral, D. Mazon, S. Mazzi, C. Mazzotta, G. McArdle, R. McDermott, K. McKay, A.G. Meigs, C. Meineri, A. Mele, V. Menkovski, S. Menmuir, A. Merle, H. Meyer, K. Mikszuta Michalik, D. Milanesio, F. Militello, A. Milocco, I.G. Miron, J. Mitchell, R. Mitteau, V. Mitterauer, J. Mlynar, V. Moiseenko, P. Molna, F. Mombelli, C. Monti, A. Montisci, J. Morales, P. Moreau, J.M. Moret, A. Moro, D. Moulton, P. Mulholland, M. Muraglia, A. Murari, A. Muraro, P. Muscente, D. Mykytchuk, F. Nabais, Y. Nakeva, F. Napoli, E. Nardon, M.F. Nave, R.D. Nem, A. Nielsen, S.K. Nielsen, M. Nocente, R. Nouailletas, S. Nowak, H. Nyström, R. Ochoukov, N. Offeddu, S. Olasz, C. Olde, F. Oliva, D. Oliveira, H.J.C. Oliver, P. Ollus, J. Ongena, F.P. Orsitto, N. Osborne, R. Otin, P. Oyola Dominguez, D.I. Palade, S. Palomba, O. Pan, N. Panadero, E. Panontin, A. Papadopoulos, P. Papagiannis, G. Papp, V.V. Parail, C. Pardanaud, J. Parisi, A. Parrott, K. Paschalidis, M. Passoni, F. Pastore, A. Patel, B. Patel, A. Pau, G. Pautasso, R. Pavlichenko, E. Pawelec, B. Pegourie, G. Pelka, E. Peluso, A. Perek, E. Perelli Cippo, C. Perez Von Thun, P. Petersson, G. Petravich, Y. Peysson, V. Piergotti, L. Pigatto, C. Piron, L. Piron, A. Pironti, F. Pisano, U. Plank, B. Ploeckl, V. Plyusnin, A. Podolnik, Y. Poels, G. Pokol, J. Poley, G. Por, M. Poradzinski, F. Porcelli, L. Porte, C. Possieri, A. Poulsen, I. Predebon, G. Pucella, M. Pueschel, P. Puglia, O. Putignano, T. Pütterich, V. Quadri, A. Quercia, M. Rabinski, L. Radovanovic, R. Ragona, H. Raj, M. Rasinski, J. Rasmussen, G. Ratta, S. Ratynskaia, R. Rayaprolu, M. Rebai, A. Redl, D. Rees, D. Refy, M. Reich, H. Reimerdes, B.C.G. Reman, O. Renders, C. Reux, D. Ricci, M. Richou, S. Rienacker, D. Rigamonti, F. Rigollet, F.G. Rimini, D. Ripamonti, N. Rispoli, N. Rivals, J.F. Rivero Rodriguez, C. Roach, G. Rocchi, S. Rode, P. Rodrigues, J. Romazanov, C.F. Romero Madrid, J. Rosato, R. Rossi, G. Rubino, J. Rueda Rueda, J. Ruiz Ruiz, P. Ryan, D. Ryan, S. Saarelma, R. Sabot, M. Salewski, A. Salmi, L. Sanchis, A. Sand, J. Santos, K. Särkimäki, M. Sassano, O. Sauter, G. Schettini, S. Schmuck, P. Schneider, N. Schoonheere, R. Schramm, R. Schrittwieser, C. Schuster, N. Schwarz, F. Sciortino, M. Scotto D’Abusco, S. Scully, A. Selce, L. Senni, M. Senstius, G. Sergienko, S.E. Sharapov, R. Sharma, A. Shaw, U. Sheikh, G. Sias, B. Sieglin, S.A. Silburn, C. Silva, A. Silva, D. Silvagni, B. Simmendefeldt Schmidt, L. Simons, J. Simpson, L. Singh, S. Sipilä, Y. Siusko, S. Smith, A. Snicker, E.R. Solano, V. Solokha, M. Sos, C. Sozzi, F. Spineanu, G. Spizzo, M. Spolaore, L. Spolladore, C. Srinivasan, A. Stagni, Z. Stancar, G. Stankunas, J. Stober, P. Strand, C.I. Stuart, F. Subba, G.Y. Sun, H.J. Sun, W. Suttrop, J. Svoboda, T. Szepesi, G. Szepesi, B. Tal, T. Tala, P. Tamain, G. Tardini, M. Tardocchi, D. Taylor, G. Telesca, A. Tenaglia, A. Terra, D. Terranova, D. Testa, C. Theiler, E. Tholerus, B. Thomas, E. Thoren, A. Thornton, A. Thrysoe, Q. TICHIT, W. Tierens, A. Titarenko, P. Tolias, E. Tomasina, M. Tomes, E. Tonello, A. Tookey, M. Toscano Jiménez, C. Tsironis, C. Tsui, A. Tykhyy, M. Ugoletti, M. Usoltseva, D.F. Valcarcel, A. Valentini, M. Valisa, M. Vallar, M. Valovic, SI. Valvis, M. van Berkel, D. Van Eester, S. Van Mulders, M. van Rossem, R. Vann, B. Vanovac, J. Varela Rodriguez, J. Varje, S. Vartanian, M. Vecsei, L. Velarde Gallardo, M. Veranda, T. Verdier, G. Verdoolaege, K. Verhaegh, L. Vermare, G. Verona Rinati, J. Vicente, E. Viezzer, L. Vignitchouk, F. Villone, B. Vincent, P. Vincenzi, M.O. Vlad, G. Vogel, I. Voitsekhovitch, I. Voldiner, P. Vondracek, N.M.T. VU, T. Vuoriheimo, C. Wade, E. Wang, T. Wauters, M. Weiland, H. Weisen, N. Wendler, D. Weston, A. Widdowson, S. Wiesen, M. Wiesenberger, T. Wijkamp, M. Willensdorfer, T. Wilson, A. Wojenski, C. Wuethrich, I. Wyss, L. Xiang, S. Xu, D. Yadykin, Y. Yakovenko, H. Yang, V. Yanovskiy, R. Yi, B. Zaar, G. Zadvitskiy, L. Zakharov, P. Zanca, D. Zarzoso, Y. Zayachuk, J. Zebrowski, M. Zerbini, P. Zestanakis, C. F. B. Zimmermann, M. Zlobinski, A. Zohar, V.K. Zotta, X. Zou, M. Zuin, M. Zurita, and I. Zychor
Subjects: JET, ASDEX Upgrade, MAST-U, TCV, WEST, Tokamak Exploitation Task Force, Nuclear and particle physics. Atomic energy. Radioactivity, QC770-798
Abstract: Within the 9th European Framework programme, since 2021 EUROfusion is operating five tokamaks under the auspices of a single Task Force called ‘Tokamak Exploitation’. The goal is to benefit from the complementary capabilities of each machine in a coordinated way and help in developing a scientific output scalable to future largre machines. The programme of this Task Force ensures that ASDEX Upgrade, MAST-U, TCV, WEST and JET (since 2022) work together to achieve the objectives of Missions 1 and 2 of the EUROfusion Roadmap: i) demonstrate plasma scenarios that increase the success margin of ITER and satisfy the requirements of DEMO and, ii) demonstrate an integrated approach that can handle the large power leaving ITER and DEMO plasmas. The Tokamak Exploitation task force has therefore organized experiments on these two missions with the goal to strengthen the physics and operational basis for the ITER baseline scenario and for exploiting the recent plasma exhaust enhancements in all four devices (PEX: Plasma EXhaust) for exploring the solution for handling heat and particle exhaust in ITER and develop the conceptual solutions for DEMO. The ITER Baseline scenario has been developed in a similar way in ASDEX Upgrade, TCV and JET. Key risks for ITER such as disruptions and run-aways have been also investigated in TCV, ASDEX Upgrade and JET. Experiments have explored successfully different divertor configurations (standard, super-X, snowflakes) in MAST-U and TCV and studied tungsten melting in WEST and ASDEX Upgrade. The input from the smaller devices to JET has also been proven successful to set-up novel control schemes on disruption avoidance and detachment.
Published: 2024
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6. Overview of T and D–T results in JET with ITER-like wall

Author: C.F. Maggi, D. Abate, N. Abid, P. Abreu, O. Adabonyan, M. Afzal, I. Ahmad, M. Akhtar, R. Albanese, S. Aleiferis, E. Alessi, P. Aleynikov, J. Alguacil, J. Alhage, M. Ali, H. Allen, M. Allinson, M. Alonzo, E. Alves, R. Ambrosino, E. Andersson Sundén, P. Andrew, M. Angelone, C. Angioni, I. Antoniou, L. Appel, C. Appelbee, C. Aramunde, M. Ariola, G. Arnoux, G. Artaserse, J.-F. Artaud, W. Arter, V. Artigues, F.J. Artola, A. Ash, O. Asztalos, D. Auld, F. Auriemma, Y. Austin, L. Avotina, J. Ayllón, E. Aymerich, A. Baciero, L. Bähner, F. Bairaktaris, I. Balboa, M. Balden, N. Balshaw, V.K. Bandaru, J. Banks, A. Banon Navarro, C. Barcellona, O. Bardsley, M. Barnes, R. Barnsley, M. Baruzzo, M. Bassan, A. Batista, P. Batistoni, L. Baumane, B. Bauvir, L. Baylor, C. Bearcroft, P. Beaumont, D. Beckett, A. Begolli, M. Beidler, N. Bekris, M. Beldishevski, E. Belli, F. Belli, S. Benkadda, J. Bentley, E. Bernard, J. Bernardo, M. Bernert, M. Berry, L. Bertalot, H. Betar, M. Beurskens, P.G. Bhat, S. Bickerton, J. Bielecki, T. Biewer, R. Bilato, P. Bílková, G. Birkenmeier, R. Bisson, J.P.S. Bizarro, P. Blatchford, A. Bleasdale, V. Bobkov, A. Boboc, A. Bock, G. Bodnar, P. Bohm, L. Bonalumi, N. Bonanomi, D. Bonfiglio, X. Bonnin, P. Bonofiglo, J. Booth, D. Borba, D. Borodin, I. Borodkina, T.O.S.J. Bosman, C. Bourdelle, M. Bowden, I. Božičević Mihalić, S.C. Bradnam, B. Breizman, S. Brezinsek, D. Brida, M. Brix, P. Brown, D. Brunetti, M. Buckley, J. Buermans, H. Bufferand, P. Buratti, A. Burckhart, A. Burgess, A. Buscarino, A. Busse, D. Butcher, G. Calabrò, L. Calacci, R. Calado, R. Canavan, B. Cannas, M. Cannon, M. Cappelli, S. Carcangiu, P. Card, A. Cardinali, S. Carli, P. Carman, D. Carnevale, B. Carvalho, I.S. Carvalho, P. Carvalho, I. Casiraghi, F.J. Casson, C. Castaldo, J.P. Catalan, N. Catarino, F. Causa, M. Cavedon, M. Cecconello, L. Ceelen, C.D. Challis, B. Chamberlain, R. Chandra, C.S. Chang, A. Chankin, B. Chapman, P. Chauhan, M. Chernyshova, A. Chiariello, G.-C. Chira, P. Chmielewski, A. Chomiczewska, L. Chone, J. Cieslik, G. Ciraolo, D. Ciric, J. Citrin, Ł. Ciupinski, R. Clarkson, M. Cleverly, P. Coates, V. Coccorese, R. Coelho, J.W. Coenen, I.H. Coffey, A. Colangeli, L. Colas, J. Collins, S. Conroy, C. Contré, N.J. Conway, D. Coombs, P. Cooper, S. Cooper, L. Cordaro, C. Corradino, Y. Corre, G. Corrigan, D. Coster, T. Craciunescu, S. Cramp, D. Craven, R. Craven, G. Croci, D. Croft, K. Crombé, T. Cronin, N. Cruz, A. Cufar, A. Cullen, A. Dal Molin, S. Dalley, P. David, A. Davies, J. Davies, S. Davies, G. Davis, K. Dawson, S. Dawson, I. Day, G. De Tommasi, J. Deane, M. Dearing, M. De Bock, J. Decker, R. Dejarnac, E. Delabie, E. de la Cal, E. de la Luna, D. Del Sarto, A. Dempsey, W. Deng, A. Dennett, G.L. Derks, G. De Temmerman, F. Devasagayam, P. de Vries, P. Devynck, A. di Siena, D. Dickinson, T. Dickson, M. Diez, P. Dinca, T. Dittmar, L. Dittrich, J. Dobrashian, T. Dochnal, A.J.H. Donné, W. Dorland, S. Dorling, S. Dormido-Canto, R. Dotse, D. Douai, S. Dowson, R. Doyle, M. Dreval, P. Drews, G. Drummond, Ph. Duckworth, H.G. Dudding, R. Dumont, P. Dumortier, D. Dunai, T. Dunatov, M. Dunne, I. Ďuran, F. Durodié, R. Dux, T. Eade, E. Eardley, J. Edwards, T. Eich, A. Eksaeva, H. El-Haroun, R.D. Ellis, G. Ellwood, C. Elsmore, S. Emery, G. Ericsson, B. Eriksson, F. Eriksson, J. Eriksson, L.G. Eriksson, S. Ertmer, G. Evans, S. Evans, E. Fable, D. Fagan, M. Faitsch, D. Fajardo Jimenez, M. Falessi, A. Fanni, T. Farmer, I. Farquhar, B. Faugeras, S. Fazinić, N. Fedorczak, K. Felker, R. Felton, H. Fernandes, D.R. Ferreira, J. Ferreira, G. Ferrò, J. Fessey, O. Février, O. Ficker, A.R. Field, A. Figueiredo, J. Figueiredo, A. Fil, N. Fil, P. Finburg, U. Fischer, G. Fishpool, L. Fittill, M. Fitzgerald, D. Flammini, J. Flanagan, S. Foley, N. Fonnesu, M. Fontana, J.M. Fontdecaba, L. Fortuna, E. Fortuna-Zalesna, M. Fortune, C. Fowler, P. Fox, O. Franklin, E. Fransson, L. Frassinetti, R. Fresa, D. Frigione, T. Fülöp, M. Furseman, S. Gabriellini, D. Gadariya, S. Gadgil, K. Gál, S. Galeani, A. Galkowski, D. Gallart, M. Gambrioli, T. Gans, J. Garcia, M. García-Muñoz, L. Garzotti, J. Gaspar, R. Gatto, P. Gaudio, D. Gear, T. Gebhart, S. Gee, M. Gelfusa, R. George, S.N. Gerasimov, R. Gerru, G. Gervasini, M. Gethins, Z. Ghani, M. Gherendi, P.-I. Gherghina, F. Ghezzi, L. Giacomelli, C. Gibson, L. Gil, M.R. Gilbert, A. Gillgren, E. Giovannozzi, C. Giroud, G. Giruzzi, J. Goff, V. Goloborodko, R. Gomes, J.-F. Gomez, B. Gonçalves, M. Goniche, J. Gonzalez-Martin, A. Goodyear, S. Gore, G. Gorini, T. Görler, N. Gotts, E. Gow, J.P. Graves, J. Green, H. Greuner, E. Grigore, F. Griph, W. Gromelski, M. Groth, C. Grove, R. Grove, N. Gupta, S. Hacquin, L. Hägg, A. Hakola, M. Halitovs, J. Hall, C.J. Ham, M. Hamed, M.R. Hardman, Y. Haresawa, G. Harrer, J.R. Harrison, D. Harting, D.R. Hatch, T. Haupt, J. Hawes, N.C. Hawkes, J. Hawkins, S. Hazael, J. Hearmon, P. Heesterman, P. Heinrich, M. Held, W. Helou, O. Hemming, S.S. Henderson, R. Henriques, R.B. Henriques, D. Hepple, J. Herfindal, G. Hermon, J.C. Hillesheim, K. Hizanidis, A. Hjalmarsson, A. Ho, J. Hobirk, O. Hoenen, C. Hogben, A. Hollingsworth, S. Hollis, E. Hollmann, M. Hölzl, M. Hook, M. Hoppe, J. Horáček, N. Horsten, A. Horton, L.D. Horton, L. Horvath, S. Hotchin, Z. Hu, Z. Huang, E. Hubenov, A. Huber, V. Huber, T. Huddleston, G.T.A. Huijsmans, Y. Husain, P. Huynh, A. Hynes, D. Iglesias, M.V. Iliasova, M. Imríšek, J. Ingleby, P. Innocente, V. Ioannou-Sougleridis, N. Isernia, I. Ivanova-Stanik, E. Ivings, S. Jachmich, T. Jackson, A.S. Jacobsen, P. Jacquet, H. Järleblad, A. Järvinen, F. Jaulmes, N. Jayasekera, F. Jenko, I. Jepu, E. Joffrin, T. Johnson, J. Johnston, C. Jones, E. Jones, G. Jones, L. Jones, T.T.C. Jones, A. Joyce, M. Juvonen, A. Kallenbach, P. Kalnina, D. Kalupin, P. Kanth, A. Kantor, A. Kappatou, O. Kardaun, J. Karhunen, E. Karsakos, Ye.O. Kazakov, V. Kazantzidis, D.L. Keeling, W. Kelly, M. Kempenaars, D. Kennedy, K. Khan, E. Khilkevich, C. Kiefer, H.-T. Kim, J. Kim, S.H. Kim, D.B. King, D.J. Kinna, V.G. Kiptily, A. Kirjasuo, K.K. Kirov, A. Kirschner, T. Kiviniemi, G. Kizane, C. Klepper, A. Klix, G. Kneale, M. Knight, P. Knight, R. Knights, S. Knipe, U. Knoche, M. Knolker, M. Kocan, F. Köchl, G. Kocsis, J.T.W. Koenders, Y. Kolesnichenko, Y. Kominis, M. Kong, B. Kool, V. Korovin, S.B. Korsholm, B. Kos, D. Kos, M. Koubiti, Y. Kovtun, E. Kowalska-Strzęciwilk, K. Koziol, Y. Krasikov, A. Krasilnikov, V. Krasilnikov, M. Kresina, A. Kreter, K. Krieger, A. Krivska, U. Kruezi, I. Książek, H. Kumpulainen, B. Kurzan, S. Kwak, O.J. Kwon, B. Labit, M. Lacquaniti, A. Lagoyannis, L. Laguardia, A. Laing, V. Laksharam, N. Lam, H.T. Lambertz, B. Lane, M. Langley, E. Lascas Neto, E. Łaszyńska, K.D. Lawson, A. Lazaros, E. Lazzaro, G. Learoyd, C. Lee, K. Lee, S. Leerink, T. Leeson, X. Lefebvre, H.J. Leggate, J. Lehmann, M. Lehnen, D. Leichtle, F. Leipold, I. Lengar, M. Lennholm, E. Leon Gutierrez, L.A. Leppin, E. Lerche, A. Lescinskis, S. Lesnoj, L. Lewin, J. Lewis, J. Likonen, Ch. Linsmeier, X. Litaudon, E. Litherland-Smith, F. Liu, T. Loarer, A. Loarte, R. Lobel, B. Lomanowski, P.J. Lomas, J. Lombardo, R. Lorenzini, S. Loreti, V.P. Loschiavo, M. Loughlin, T. Lowe, C. Lowry, T. Luce, R. Lucock, T. Luda Di Cortemiglia, M. Lungaroni, C.P. Lungu, T. Lunt, V. Lutsenko, B. Lyons, J. Macdonald, E. Macusova, R. Mäenpää, H. Maier, J. Mailloux, S. Makarov, P. Manas, A. Manning, P. Mantica, M.J. Mantsinen, J. Manyer, A. Manzanares, Ph. Maquet, M. Maraschek, G. Marceca, G. Marcer, C. Marchetto, O. Marchuk, A. Mariani, G. Mariano, M. Marin, A. Marin Roldan, M. Marinelli, T. Markovič, L. Marot, C. Marren, S. Marsden, S. Marsen, J. Marsh, R. Marshall, L. Martellucci, A.J. Martin, C. Martin, R. Martone, S. Maruyama, M. Maslov, M. Mattei, G.F. Matthews, D. Matveev, E. Matveeva, A. Mauriya, F. Maviglia, M. Mayer, M.-L. Mayoral, S. Mazzi, C. Mazzotta, R. McAdams, P.J. McCarthy, P. McCullen, R. McDermott, D.C. McDonald, D. McGuckin, V. McKay, L. McNamee, A. McShee, D. Mederick, M. Medland, S. Medley, K. Meghani, A.G. Meigs, S. Meitner, S. Menmuir, K. Mergia, S. Mianowski, P. Middleton, J. Mietelski, K. Mikszuta-Michalik, D. Milanesio, E. Milani, E. Militello-Asp, F. Militello, J. Milnes, A. Milocco, S. Minucci, I. Miron, J. Mitchell, J. Mlynář, V. Moiseenko, P. Monaghan, I. Monakhov, A. Montisci, S. Moon, R. Mooney, S. Moradi, R.B. Morales, L. Morgan, F. Moro, J. Morris, T. Mrowetz, L. Msero, S. Munot, A. Muñoz-Perez, M. Muraglia, A. Murari, A. Muraro, B. N’Konga, Y.S. Na, F. Nabais, R. Naish, F. Napoli, E. Nardon, V. Naulin, M.F.F. Nave, R. Neu, S. Ng, M. Nicassio, D. Nicolai, A.H. Nielsen, S.K. Nielsen, D. Nina, C. Noble, C.R. Nobs, M. Nocente, H. Nordman, S. Nowak, H. Nyström, J. O’Callaghan, M. O’Mullane, C. O’Neill, C. Olde, H.J.C. Oliver, R. Olney, J. Ongena, G.P. Orsitto, A. Osipov, R. Otin, N. Pace, L.W. Packer, E. Pajuste, D. Palade, J. Palgrave, O. Pan, N. Panadero, T. Pandya, E. Panontin, A. Papadopoulos, G. Papadopoulos, G. Papp, V.V. Parail, A. Parsloe, K. Paschalidis, M. Passeri, A. Patel, A. Pau, G. Pautasso, R. Pavlichenko, A. Pavone, E. Pawelec, C. Paz-Soldan, A. Peacock, M. Pearce, I.J. Pearson, E. Peluso, C. Penot, K. Pepperell, A. Perdas, T. Pereira, E. Perelli Cippo, C. Perez von Thun, D. Perry, P. Petersson, G. Petravich, N. Petrella, M. Peyman, L. Pigatto, M. Pillon, S. Pinches, G. Pintsuk, C. Piron, A. Pironti, F. Pisano, R. Pitts, U. Planck, N. Platt, V. Plyusnin, M. Podesta, G. Pokol, F.M. Poli, O.G. Pompilian, M. Poradzinski, M. Porkolab, C. Porosnicu, G. Poulipoulis, A.S. Poulsen, I. Predebon, A. Previti, D. Primetzhofer, G. Provatas, G. Pucella, P. Puglia, K. Purahoo, O. Putignano, T. Pütterich, A. Quercia, G. Radulescu, V. Radulovic, R. Ragona, M. Rainford, P. Raj, M. Rasinski, D. Rasmussen, J. Rasmussen, J.J. Rasmussen, A. Raso, G. Rattá, S. Ratynskaia, R. Rayaprolu, M. Rebai, A. Redl, D. Rees, D. Réfy, R. Reichle, H. Reimerdes, B.C.G. Reman, C. Reux, S. Reynolds, D. Rigamonti, E. Righi, F.G. Rimini, J. Risner, J.F. Rivero-Rodriguez, C.M. Roach, J. Roberts, R. Robins, S. Robinson, D. Robson, S. Rode, P. Rodrigues, P. Rodriguez-Fernandez, S. Romanelli, J. Romazanov, E. Rose, C. Rose-Innes, R. Rossi, S. Rowe, D. Rowlands, C. Rowley, M. Rubel, G. Rubinacci, G. Rubino, M. Rud, J. Ruiz Ruiz, F. Ryter, S. Saarelma, A. Sahlberg, M. Salewski, A. Salmi, R. Salmon, F. Salzedas, F. Sanchez, I. Sanders, D. Sandiford, F. Sanni, O. Sauter, P. Sauvan, G. Schettini, A. Shevelev, A.A. Schekochihin, K. Schmid, B.S. Schmidt, S. Schmuck, M. Schneider, P.A. Schneider, N. Schoonheere, R. Schramm, D. Scoon, S. Scully, M. Segato, J. Seidl, L. Senni, J. Seo, G. Sergienko, M. Sertoli, S.E. Sharapov, R. Sharma, A. Shaw, R. Shaw, H. Sheikh, U. Sheikh, N. Shi, P. Shigin, D. Shiraki, G. Sias, M. Siccinio, B. Sieglin, S.A. Silburn, A. Silva, C. Silva, J. Silva, D. Silvagni, D. Simfukwe, J. Simpson, P. Sirén, A. Sirinelli, H. Sjöstrand, N. Skinner, J. Slater, T. Smart, R.D. Smirnov, N. Smith, P. Smith, T. Smith, J. Snell, L. Snoj, E.R. Solano, V. Solokha, C. Sommariva, K. Soni, M. Sos, J. Sousa, C. Sozzi, T. Spelzini, F. Spineanu, L. Spolladore, D. Spong, C. Srinivasan, G. Staebler, A. Stagni, I. Stamatelatos, M.F. Stamp, Ž. Štancar, P.A. Staniec, G. Stankūnas, M. Stead, B. Stein-Lubrano, A. Stephen, J. Stephens, P. Stevenson, C. Steventon, M. Stojanov, D.A. St-Onge, P. Strand, S. Strikwerda, C.I. Stuart, S. Sturgeon, H.J. Sun, S. Surendran, W. Suttrop, J. Svensson, J. Svoboda, R. Sweeney, G. Szepesi, M. Szoke, T. Tadić, B. Tal, T. Tala, P. Tamain, K. Tanaka, W. Tang, G. Tardini, M. Tardocchi, D. Taylor, A.S. Teimane, G. Telesca, A. Teplukhina, A. Terra, D. Terranova, N. Terranova, D. Testa, B. Thomas, V.K. Thompson, A. Thorman, A.S. Thrysoe, W. Tierens, R.A. Tinguely, A. Tipton, H. Todd, M. Tomeš, A. Tookey, P. Tsavalas, D. Tskhakaya, L.-P. Turică, A. Turner, I. Turner, M. Turner, M.M. Turner, G. Tvalashvili, A. Tykhyy, S. Tyrrell, A. Uccello, V. Udintsev, A. Vadgama, D.F. Valcarcel, A. Valentini, M. Valisa, M. Vallar, M. Valovic, M. Van Berkel, K.L. van de Plassche, M. van Rossem, D. Van Eester, J. Varela, J. Varje, T. Vasilopoulou, G. Vayakis, M. Vecsei, J. Vega, M. Veis, P. Veis, S. Ventre, M. Veranda, G. Verdoolaege, C. Verona, G. Verona Rinati, E. Veshchev, N. Vianello, E. Viezzer, L. Vignitchouk, R. Vila, R. Villari, F. Villone, P. Vincenzi, A. Vitins, Z. Vizvary, M. Vlad, I. Voldiner, U. Von Toussaint, P. Vondráček, B. Wakeling, M. Walker, R. Walker, M. Walsh, R. Walton, E. Wang, F. Warren, R. Warren, J. Waterhouse, C. Watts, T. Webster, M. Weiland, H. Weisen, M. Weiszflog, N. Wendler, A. West, M. Wheatley, S. Whetham, A. Whitehead, D. Whittaker, A. Widdowson, S. Wiesen, M. Willensdorfer, J. Williams, I. Wilson, T. Wilson, M. Wischmeier, A. Withycombe, D. Witts, A. Wojcik-Gargula, E. Wolfrum, R. Wood, R. Woodley, R. Worrall, I. Wyss, T. Xu, D. Yadykin, Y. Yakovenko, Y. Yang, V. Yanovskiy, R. Yi, I. Young, R. Young, B. Zaar, R.J. Zabolockis, L. Zakharov, P. Zanca, A. Zarins, D. Zarzoso Fernandez, K.-D. Zastrow, Y. Zayachuk, M. Zerbini, W. Zhang, B. Zimmermann, M. Zlobinski, A. Zocco, V.K. Zotta, M. Zuin, W. Zwingmann, and I. Zychor
Subjects: magnetic fusion, JET-ILW, D–T, tritium, alpha particles, fusion prediction, Nuclear and particle physics. Atomic energy. Radioactivity, QC770-798
Abstract: In 2021 JET exploited its unique capabilities to operate with T and D–T fuel with an ITER-like Be/W wall (JET-ILW). This second major JET D–T campaign (DTE2), after DTE1 in 1997, represented the culmination of a series of JET enhancements—new fusion diagnostics, new T injection capabilities, refurbishment of the T plant, increased auxiliary heating, in-vessel calibration of 14 MeV neutron yield monitors—as well as significant advances in plasma theory and modelling in the fusion community. DTE2 was complemented by a sequence of isotope physics campaigns encompassing operation in pure tritium at high T-NBI power. Carefully conducted for safe operation with tritium, the new T and D–T experiments used 1 kg of T (vs 100 g in DTE1), yielding the most fusion reactor relevant D–T plasmas to date and expanding our understanding of isotopes and D–T mixture physics. Furthermore, since the JET T and DTE2 campaigns occurred almost 25 years after the last major D–T tokamak experiment, it was also a strategic goal of the European fusion programme to refresh operational experience of a nuclear tokamak to prepare staff for ITER operation. The key physics results of the JET T and DTE2 experiments, carried out within the EUROfusion JET1 work package, are reported in this paper. Progress in the technological exploitation of JET D–T operations, development and validation of nuclear codes, neutronic tools and techniques for ITER operations carried out by EUROfusion (started within the Horizon 2020 Framework Programme and continuing under the Horizon Europe FP) are reported in (Litaudon et al Nucl. Fusion accepted), while JET experience on T and D–T operations is presented in (King et al Nucl. Fusion submitted).
Published: 2024
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7. Analysis of fusion alphas interaction with RF waves in D-T plasma at JET

Author: K.K. Kirov, F. Auriemma, P.J. Bonofiglo, C.D. Challis, E. De la Luna, J. Eriksson, D. Gallart, J. Garcia, M. Gorelenkova, J. Hobirk, P. Jacquet, A. Kappatou, Y. Kazakov, D. Keeling, D. King, V. Kiptily, E. Lerche, C. Maggi, J. Mailloux, P. Mantica, M. Mantsinen, M. Maslov, S. Menmuir, R. Sharma, P. Siren, Z. Stancar, D. Van Eester, and JET Contributors
Subjects: JET, DT plasma, alphas, synergistic effects, ICRH, Nuclear and particle physics. Atomic energy. Radioactivity, QC770-798
Abstract: This work studies the influence of radio frequency (RF) waves in the ion cyclotron resonance heating (ICRH) range of frequencies on fusion alphas during the recent JET D-T campaign. Fusion alphas from D-T reactions are created with energies of about 3.5 MeV and therefore have significant Doppler shifts enabling synergistic interactions between them and RF waves at a broad range of frequencies, including the ones foreseen for future fusion machines in ITER (Schneider et al 2021 Nucl. Fusion 61 126058) and SPARC (Creely et al 2020 J. Plasma Phys. 86 865860502). Resonant interactions between RF waves and alphas, also called synergistic effects, will modify the alpha distribution and ultimately will have an impact on alpha orbit losses and heating. Data from JET 3.43 T/2.3 MA pulses based on the hybrid scenario (Hobirk et al 2023 Nucl. Fusion ; Hobirk et al 29th IAEA FEC23 Conf. ( 16–21 October 2023 ); Challis et al 48th EPS Conf. on Plasma Physics ( 27 June–1 July 2022 ) during the DTE2 campaign (Maggi et al 2023 Nucl. Fusion )) were used for the analysis in this study. The impact of synergistic effects on alpha orbit losses and alpha heating are assessed. The conclusions are based on the analysis of experimental data for fast alpha losses, i.e. measurements from neutral particle analyser (NPA), fast ion losses scintillator detector, Faraday cups (FCs), and TRANSP (Hawryluk et al 1980 Physics of Plasmas Close to Thermonuclear Conditions vol 1 (CEC) pp 19–46) simulations. Experimental data and TRANSP analysis indicates that there are indeed changes in the alpha distribution function (DF) due to interaction with RF waves. Data from the NPA show increased ^4 He flux in the range from a few hundred keV up to 800 keV for pulses with RF power, while TRANSP clearly shows modifications in the fast alpha DF for these energies. Data from the scintillator detector and the FCs were compared for pulses with and without ICRH power and versus cases with enhanced alpha losses due to MHD activity. The trends from these diagnostics consistently show no additional alpha losses due to interaction with RF waves. TRANSP predictions for the impact of ynergistic effects on alpha heating show up to a 42% increase in alpha electron heating and up to a 25% increase in alpha ion heating. These effects, however, become negligibly small, less than 1%, when alpha heating is compared to the total auxiliary heating power in the investigated JET pulses.
Published: 2024
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8. Detection of alpha heating in JET-ILW DT plasmas by a study of the electron temperature response to ICRH modulation

Author: P. Mantica, F. Auriemma, I. Casiraghi, D. Gallart, K. Kirov, E. Lerche, A. Salmi, A. Dal Molin, E. Delabie, J. Eriksson, J. Garcia, P. Huynh, P. Jacquet, T. Jonsson, V. Kiptily, E. Litherland–Smith, C.F. Maggi, M. Mantsinen, G. Marcer, M. Maslov, S. Menmuir, M. Nocente, E. Peluso, G. Pucella, D. Rigamonti, Z. Stancar, H. Sun, G. Szepesi, M. Tardocchi, D. Van Eester, and JET Contributors
Subjects: tokamak, DT plasmas, alpha heating, ICRH modulation, Nuclear and particle physics. Atomic energy. Radioactivity, QC770-798
Abstract: In the JET DTE2 campaign a new method was successfully tested to detect the heating of bulk electrons by α-particles, using the dynamic response of the electron temperature T _e to the modulation of ion cyclotron resonance heating (ICRH). A fundamental deuterium (D) ICRH scheme was applied to a tritium-rich hybrid plasma with D-neutral beam injection (NBI). The modulation of the ion temperature T _i and of the ICRH accelerated deuterons leads to modulated α -heating with a large delay with respect to other modulated electron heating terms. A significant phase delay of ∼40° is measured between central T _e and T _i , which can only be explained by α -particle heating. Integrated modelling using different models for ICRH absorption and ICRH/NBI interaction reproduces the effect qualitatively. Best agreement with experiment is obtained with the European Transport Solver/Heating and Current Drive workflow.
Published: 2024
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9. Observation of alpha-particles in recent D–T experiments on JET

Author: V.G. Kiptily, C.D. Challis, R. Dumont, M. Fitzgerald, J. Garcia, L. Garzotti, Z. Ghani, J. Hobirk, P. Jacquet, A. Kappatou, D. Keeling, Ye. Kazakov, P. Mantica, M.J. Mantsinen, S.E. Sharapov, E.R. Solano, D. Van Eester, P.J. Bonofiglo, T. Craciunescu, A. Dal Molin, J. Eriksson, V. Goloborodko, M.V. Iliasova, E.M. Khilkevitch, D. King, I. Lengar, M. Nocente, S. Menmuir, M. Podestà, M. Poradzinski, D. Rigamonti, J. Rivero-Rodriguez, Z. Stancar, A.E. Shevelev, P. Siren, H. Sun, D.M. Taylor, M. Tardocchi, P. Beaumont, F. Belli, F.E. Cecil, R. Coelho, M. Curuia, M. Garcia-Munoz, E. Joffrin, C. Lowry, M. Lennholm, E. Lerche, C.F. Maggi, J. Mailloux, D. Marocco, M. Maslov, C. Perez Von Thun, F. Rimini, V. Zoita, and JET Contributors
Subjects: JET, DT-plasmas, fusion, alpha-particles, Nuclear and particle physics. Atomic energy. Radioactivity, QC770-798
Abstract: The fusion reaction between deuterium and tritium, D ( T,n ) ^4 He is the main source of energy in future thermonuclear reactors. Alpha-particles ( ^4 He -ions) born with an average energy of 3.5 MeV transferring energy to the thermal plasma during their slowing down, should provide the self-sustained D–T plasma burn. The adequate confinement of α -particles is essential to provide efficient heating of the bulk plasma and steady burning of a reactor plasma. That is why the fusion-born α -particle studies have been a priority task in the second D–T experiments (DTE2) on the Joint European Torus (JET) to understand the main mechanisms of their slowing down, redistribution and losses and to develop optimal plasma scenarios. JET with Be -wall and W -divertor, enhanced auxiliary heating systems and improved energetic-particle diagnostic capabilities, producing significant population of α -particles, provided the possibility for comprehensive studying of the α -particle behaviour. Selected results of the confined and lost α -particle measurements, evidence of α -particle self-heating and assessments of the fusion performance are presented in this paper giving an opportunity for further modelling and extrapolation to the International Thermonuclear Experimental Reactor and burning plasma reactors.
Published: 2024
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10. Helium plasma operations on ASDEX Upgrade and JET in support of the non-nuclear phases of ITER

Author: A. Hakola, M. Balden, M. Baruzzo, R. Bisson, S. Brezinsek, T. Dittmar, D. Douai, M. Dunne, L. Garzotti, M. Groth, R. Henriques, L. Horvath, I. Jepu, E. Joffrin, A. Kappatou, D. Keeling, K. Krieger, B. Labit, M. Lennholm, J. Likonen, A. Loarte, P. Lomas, C. Lowry, M. Maslov, D. Matveev, R.A. Pitts, U. Plank, M. Rasinski, D. Ryan, S. Saarelma, S. Silburn, E.R. Solano, W. Suttrop, T. Tala, E. Tsitrone, N. Vianello, T. Wauters, A. Widdowson, M. Wischmeier, the EUROfusion Tokamak Exploitation Team, the ASDEX Upgrade Team, and JET Contributors
Subjects: helium plasma, H-mode, tungsten fuzz, erosion, Nuclear and particle physics. Atomic energy. Radioactivity, QC770-798
Abstract: For its initial operational phase, ITER has until recently considered using non-nuclear hydrogen (H) or helium (He) plasmas to keep nuclear activation at low levels. To this end, the Tokamak Exploitation Task Force of the EUROfusion Consortium carried out dedicated experimental campaigns in He on the ASDEX Upgrade (AUG) and JET tokamaks in 2022, with particular emphasis put on the ELMy H-mode operation and plasma-wall interaction processes as well as comparison to H or deuterium (D) plasmas. Both in pure He and mixed He + H plasmas, H-mode operation could be reached but more effort was needed to obtain a stable plasma scenario than in H or D. Even if the power threshold for the LH transition was lower in He, entering the type-I ELMy regime appeared to require equally much or even more heating power than in H. Suppression of ELMs by resonant magnetic perturbations was studied on AUG but was only possible in plasmas with a He content below 19%; the reason for this unexpected behaviour remains still unclear and various theoretical approaches are being pursued to properly understand the physics behind ELM suppression. The erosion rates of tungsten (W) plasma-facing components were an order of magnitude larger than what has been reported in hydrogenic plasmas, which can be attributed to the prominent role of He ^2+ ions in the plasma. For the first time, the formation of nanoscale structures (W fuzz) was unambiguously demonstrated in H-mode He plasmas on AUG. However, no direct evidence of fuzz creation on JET was obtained despite the main conditions for its occurrence being met. The reason could be a delicate balance between W erosion by ELMs, competition between the growth and annealing of the fuzz, and coverage of the surface with co-deposits.
Published: 2024
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11. Alpha particle loss measurements and analysis in JET DT plasmas

Author: P.J. Bonofiglo, V.G. Kiptily, J. Rivero-Rodriguez, M. Nocente, M. Podestà, Ž. Štancar, M. Poradzinski, V. Goloborodko, S.E. Sharapov, M. Fitzgerald, R. Dumont, J. Garcia, D. Keeling, D. Frigione, L. Garzotti, F.G. Rimini, D. Van Eester, E. Lerche, M. Maslov, and JET Contributors
Subjects: alpha particles, alpha physics, DT plasmas, fast ion losses, MHD, Nuclear and particle physics. Atomic energy. Radioactivity, QC770-798
Abstract: Burning reactor plasmas will be self-heated by fusion born alpha particles from deuterium-tritium reactions. Consequently, a thorough understanding of the confinement and transport of DT-born alpha particles is necessary to maintain the plasma self-heating. Measurements of fast ion losses provide a direct means to monitor alpha particle confinement. JET’s 2021–2022 second experimental DT-campaign offers burning plasma scenarios with advanced fast ion loss diagnostics for the first time in nearly 25 years. Coherent and non-coherent alpha losses were observed due to a variety of low frequency MHD activity. This manuscript will present the loss mechanisms, spatial and pitch dependencies, scalings with plasma parameters, correlations with wall impurities, and magnitude of DT-alpha born losses.
Published: 2024
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12. JET machine operations in T&D-T

Author: The JET Operations Team (presented by D.B. King), E. Abdelrahman, A. Abdul Hamid, N. Abid, K. Abraham, O. Adabonyan, C. Adlam, M. Afzal, M. Akhtar, V. Aldred, S. Aldworth, S. Aleiferis, M. Ali, R. Alie, R. Allan, H. Allen, E. Alli, M. Allinson, P. Almond, J. Angus, K. Antcliffe, I. Antoniou, L. Appel, C. Appelbee, C. Aramunde, N. Archer, S. Aria, H. Arkuszynski, M. Arshad, G. Artaserse, A. Ash, C. Ashe, T. Aue, D. Auld, B. Austin, Y. Austin, C. Ayres, R.B. Morales, S. Baker, S. Bakes, I. Balboa, C. Balshaw, N. Balshaw, J. Banks, J. Banner, A. Barnard, M. Barnard, M. Baruzzo, C. Basagiannis, S. Bathe Hariyanandan, P. Batistoni, R. Baughan, P. Beaumont, D. Beckett, A. Begolli, M. Beldishevski, K. Bell, E. Belonohy, J. Bentley, J. Bernardo, M. Berry, J. Bhatt, S. Bickerton, J. Bielecki, W. Bird, D. Blackett, K. Blackman, S. Blake, P. Blatchford, A. Bleasdale, A. Boboc, J. Booth, P. Boulting, M. Bowden, C. Boyd, K. Boyd, R. Bracey, D. Brennan, A. Brett, M. Bright, M. Brix, I. Brooks, B. Brown, P. Brown, M. Brown, P. Brummitt, B. Viola, A. Buckingham, M. Buckley, J. Bumpass, M. Burford, A. Burgess, J. Burton-Sweeten, A. Busse, D. Butcher, P. Cahill, P. Camp, I. Campbell, R. Canavan, J. Cane, M. Cannon, N. Canterbury, A. Carberry, P. Card, M. Carlick, M. Carlo, P. Carman, A. Carruthers, S. Carter, I.S. Carvalho, P. Carvalho, F. Casson, D. Chalk, B. Chamberlain, P. Chauhan, A. Chow, A. Churchman, D. Ciric, M. Clark, J. Clarkson, R. Clarkson, T. Clayton, M. Cleverly, P. Coates, I. Coffey, J. Collins, S. Conroy, N.J. Conway, R. Conway, J. Cook, M. Cooke, D. Coombs, P. Cooper, S. Cooper, G. Corrigan, R. Cotterell, A. Coulson, M. Cox, S. Cox, S. Cramp, D. Craven, R. Craven, M. Crick, D. Croft, T. Cronin, Z. Cui, A. Cullen, R. Cumming, C. Cummings, A. Dal Molin, P. Dalgliesh, S. Dalley, A. Danquah, S. Davies, G. Davis, H. Dawson, K. Dawson, S. Dawson, I. Day, L. de Caires, E. de la Luna, K. Deakin, J. Deane, M. Dearing, A. Dennett, T. Dickson, J. Dobrashian, T. Dochnal, S. Dorling, D. Douai, S. Dowson, J. Drewitt, G. Drummond, P. Dumortier, R. Eade, R. Eastham, K. Eden, J. Edmond, J. Edwards, P. Edwards, H. Elamin, S. Elford, H. El-Haroun, P. Ellis, C. Elsmore, S. Emery, G. Evans, S. Evans, D. Fagan, T. Farmer, I. Farquhar, R. Felton, F. Ferner, J. Fessey, P. Finburg, G. Fishpool, L. Fittill, J. Flanagan, K. Flinders, S. Foley, M. Fontana, M. Fortune, J. Foster, C. Fowler, P. Fox, O. Franklin, R. Franklin, R. Fraser, S. French, M. Furseman, A. Gabbidon, L. Garcia, J. Garcia, M. Gardener, D. Gear, T. Gedling, S. Gee, P. Gell, R. George, S. Gerasimov, M. Gethins, Z. Ghani, L. Giacomelli, C. Gibson, V. Gilsenan, C. Giroud, R. Glen, J. Goff, C. Goodman, A. Goodyear, A. Gordon, S. Gore, S. Gosden, N. Gotts, E. Gow, W. Graham, G. Graham, M. Green, R. Gregory, R. Griffiths, T. Griffiths, F. Griph, C. Grundy, T. Grundy, D. Guard, D. Guest, C. Gurl, S. Hacquin, A. Hakola, K. Hammond, H. Harmer, P. Harper, S. Harris, D. Hart, D. Hattan, A. Haupt, J. Hawes, N. Hawkes, J. Hawkins, P. Hawkins, S. Hayes, S. Hazael, D. Heads, P. Heesterman, O. Hemming, R.B. Henriques, G. Hermon, G. Hewson, T. Hibberd, M. Hill, J. Hillesheim, I. Hirb, K. Ho, C. Hogben, A. Hollingsworth, S. Hollis, M. Hook, D. Hopley, N. Horsten, A. Horton, L.D. Horton, L. Horvath, S. Hotchin, Z. Huang, E. Hubenov, V. Huber, A. Huber, C. Huddart, T. Huddleston, T. Hunter, Y. Husain, A. Hynes, J. Ingleby, S. Ives, E. Ivings, S. Jackson, T. Jackson, P. Jacquet, N. Jayasekera, I. Jepu, D. Jezzard, E. Joffrin, R. Johnson, J. Johnston, C. Jones, E. Jones, G. Jones, L. Jones, S. Jones, T. Jones, M. Jones, A. Joyce, M. Juvonen, A. Kantor, A. Kappatou, G. Karajgikar, J. Karhunen, I. Karnowska-Paterski, E. Karsakos, G. Kaveney, G. Kay, D. Keeling, T. Keenan, R. Kelly, W. Kelly, D. Kennedy, R. Kennedy, O. Kent, K. Khan, D. King, D. Kinna, V. Kiptily, K. Kirov, G. Kneale, M. Knight, P. Knight, J. Knipe, R. Knipe, S. Knipe, P. Kochanski, D. Kos, M. Kovari, E. Kowalska-Strzęciwilk, N. Kraus, M. Kresina, B. Labit, A. Laing, V. Laksharam, N. Lam, B. Lane, C. Lane, T. Lavender, A. Lawson, K. Lawson, G. Learoyd, T. Leeson, X. Lefebvre, J. Lehmann, M. Lennholm, K. Lennon, E. Lerche, S. Lesnoj, E. Letellier, L. Lewin, J. Lewis, J. Li, G. Liddiard, E. Litherland-Smith, F. Liu, R. Lobel, J. Logan, P. Lomas, C. Long, U. Losada, C. Loveridge, T. Lowe, C. Lowry, R. Lucock, G. Lyons, J. Macdonald, P. Macheta, T. Madden, J. Maddock, C.F. Maggi, J. Mailloux, A. Manning, C. Manning, N. Mantel, A. Manzanares, S. Marsden, J. Marsh, R. Marshall, A. Martin, M. Maslov, G. Matthews, N. Mayfield, M. Mayoral, R. McAdams, L. McCafferty, P. McCullen, D. McDonald, A. McDonnell, D. McGuckin, T. McIver, V. McKay, R. McKean, L. McNamee, A. McShee, R. Meadows, D. Mederick, M. Medland, K. Meghani, A. Meigs, S. Menmuir, I. Merrigan, S. Mianowski, P. Middleton, C. Miles, J. Milnes, A. Milocco, J. Mitchell, P. Mitchell, P. Monaghan, I. Monakhov, P. Moody, R. Mooney, C. Moore, N. Mooring, L. Morgan, R. Morgan, J. Morris, O. Morton, S. Morton, P. Mulvana, S. Munot, R. Munro-Smith, K. Musgrave, R. Naish, N. Neethiraj, J. Neilson, A. Newman, S. Ng, M. Nicassio, K. Nicholls, M. Nightingale, C. Noble, R. Normington, C. Nygaard, J. O’Callaghan, R. Olney, B. O’Meara, M. O’Mullane, C. O’Neill, C. Opara, K. O’Rourke, J. Ottley, K. Otu, A. Owen, N. Pace, K. Palamartchouk, D. Paley, J. Palgrave, G. Papadopoulos, V. Parail, A. Parrott, A. Parsloe, L. Parsons, R. Parsons, A. Patel, J. Patel, A. Peacock, M. Pearce, T. Pearce, I. Pearson, J. Penzo, A. Perdas, T. Pereira, C. Perez Von Thun, D. Perry, N. Petrella, M. Peyman, N. Platt, M. Poradzinski, M. Porter, M. Porton, C. Powell, J. Pozzi, M. Price, L. Price, P. Puglia, D. Pulley, K. Purahoo, M. Rainford, A. Raj, S. Randhawa, S. Rapa, K. Ravisankar, C. Rayner, A. Read, C. Reux, S. Reynolds, V. Riccardo, L. Richiusa, D. Rigamonti, F. Rimini, J. Roberts, R. Robins, S. Robinson, T. Robinson, D. Robson, S. Romanelli, F. Rose, C. Rose-Innes, D. Rouse, S. Rowe, N. Rowland, D. Rowlands, M. Rubel, K. Sabin, R. Salmon, H. Salter, A. Sanders, E. Sanders, I. Sanders, D. Sandiford, F. Sanni, R. Sarwar, R. Sayles, C. Scaysbrook, G. Scott, D. Scraggs, S. Scully, R. Sealey, E. Searle, M. Segato, M. Sertoli, C. Shanks, R. Sharma, A. Shaw, K. Sheahan, H. Sheikh, D. Shrestha, R. Siddiqui, S. Silburn, J. Silva, D. Simfukwe, J. Simpson, M. Sinclair, A. Sips, P. Sirén, S. Skeats, N. Skinner, B. Slade, J. Slater, T. Smart, G. Smith, J. Smith, N. Smith, P. Smith, T. Smith, F. P. Smith, J. Snell, K. Snelling, K. Soare, E. Solano, A. Spelzini, C. Srinivasan, Z. Stancar, P.A. Staniec, M. Stead, R. Steadman, L. Steel, D. Steele, A. Stephen, J. Stephens, L. Stevenson, P. Stevenson, C. Steventon, L. Sticklen, M. Stojanov, S. Strikwerda, C. Stuart, G. Stubbs, N. Studd, W. Studholme, H. Sun, S. Surendran, G. Szepesi, M. Szoke, H. Tan, A. Taylor, D. Taylor, K. Taylor, A. Thingore, B. Thomas, J. Thomas, A. Thorman, A. Tilley, A. Tipton, N. Tipton, H. Todd, P. Tonner, A. Tookey, M. Towndrow, M. Tsang, E. Tsitrone, I. Turner, M. Turner, G. Tvalashvili, S. Tyrrell, A. Vadgama, D. Valcarcel, Q. Van Der Westhuizen, J. Verdon, N. Vianello, A. Vittal, Z. Vizvary, B. Wakeling, M. Walker, R. Walker, T. Wall, M. Walsh, T. Walsh, J. Walters, J. Walton, R. Walton, S. Warder, F. Warren, R. Warren, J. Waterhouse, T. Webster, G. Wells, C. Wellstood, A. West, M. Wheatley, S. Whiffin, A. Whitehead, C. Whitehead, D. Whittaker, A. Widdowson, J. Wilcox, D. Wilkins, R. Wilkins, J. Williams, M. Williams, D. Willoughby, A. Wilson, I. Wilson, T. Wilson, M. Wischmeier, P. Wise, G. Withenshaw, A. Withycombe, D. Witts, J. Witts, R. Wood, L. Woodham, C. Woodley, J. Woodley, R. Woodley, B. Woods, S. Wray, T. Xu, I. Young, R. Young, K-D. Zastrow, Y. Zayachuk, and M. Zerbini
Subjects: JET, tritium, operations, Nuclear and particle physics. Atomic energy. Radioactivity, QC770-798
Abstract: JET, the world’s largest operating tokamak with unique Be/W wall and tritium handling capability, completed a Deuterium-Tritium (D-T) campaign in 2021 (Maggi et al 29th Fusion Energy Conf. ) following a decade of preparatory experiments, dedicated enhancements, technical rehearsals and training (Horton et al 2016 Fusion Eng. Des. 109–111 925). Operation with tritium raises significant technical, safety and scientific challenges not encountered in standard protium or deuterium operation. This contribution describes the tritium operational requirements, pulses and technical preparations, new operating procedures, lessons learned and details on the achieved operational availability and performance. The preparation and execution of the recent JET tritium experiments benefitted from the previous experience in 1991 (Preliminary Tritium Experiment), 1997 (DTE1 campaign) and 2003 (Trace Tritium Campaigns) and consisted of the following five phases: technical rehearsals and scenario preparation, tritium commissioning, 100% tritium campaign, D-T campaign (DTE2), tritium clean-up. Following the clean-up JET resumed normal operation and is currently undertaking a further D-T campaign (DTE3).
Published: 2024
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13. The core–edge integrated neon-seeded scenario in deuterium–tritium at JET

Author: C. Giroud, I.S. Carvalho, S. Brezinsek, A. Huber, D. Keeling, J. Mailloux, R.A. Pitts, E. Lerche, R. Henriques, J. Hillesheim, K. Lawson, M. Marin, E. Pawelec, M. Sos, H.J. Sun, M. Tomes, S. Aleiferis, A. Bleasdale, M. Brix, A. Boboc, J. Bernardo, P. Carvalho, I. Coffey, S. Henderson, D.B. King, F. Rimini, M. Maslov, E. Alessi, T. Craciunescu, M. Fontana, J.M. Fontdecaba, L. Garzotti, Z. Ghani, L. Horvath, I. Jepu, J. Karhunen, D. Kos, E. Litherland-Smith, A. Meigs, S. Menmuir, R.B. Morales, S. Nowak, E. Peluso, T. Pereira, V. Parail, G. Petravich, G. Pucella, P. Puglia, D. Refy, S. Scully, M. Sertoli, S. Silburn, D. Taylor, B. Thomas, A. Tookey, Ž. Štancar, G. Szepesi, B. Viola, A. Widdowson, E. de la Luna, and JET Contributors
Subjects: JET, baseline, deuterium–tritium, detachment, neon, seeding, Nuclear and particle physics. Atomic energy. Radioactivity, QC770-798
Abstract: This paper reports the first experiment carried out in deuterium–tritium addressing the integration of a radiative divertor for heat-load control with good confinement. Neon seeding was carried out for the first time in a D–T plasma as part of the second D–T campaign of JET with its Be/W wall environment. The technical difficulties linked to the re-ionisation heat load are reported in T and D–T. This paper compares the impact of neon seeding on D–T plasmas and their D counterpart on the divertor detachment, localisation of the radiation, scrape-off profiles, pedestal structure, edge localised modes and global confinement.
Published: 2024
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14. Characterisation of divertor detachment onset in JET-ILW hydrogen, deuterium, tritium and deuterium–tritium low-confinement mode plasmas

Author: M. Groth, V. Solokha, S. Aleiferis, S. Brezinsek, M. Brix, I.S. Carvalho, P. Carvalho, G. Corrigan, D. Harting, N. Horsten, I. Jepu, J. Karhunen, K. Kirov, B. Lomanowski, K.D. Lawson, C. Lowry, A.G. Meigs, S. Menmuir, E. Pawelec, T. Pereira, A. Shaw, S. Silburn, B. Thomas, S. Wiesen, P. Börner, D. Borodin, S. Jachmich, D. Reiter, G. Sergienko, Z. Stancar, B. Viola, P. Beaumont, J. Bernardo, I. Coffey, N.J. Conway, E. de la Luna, D. Douai, C. Giroud, J. Hillesheim, L. Horvath, A. Huber, P. Lomas, C.F. Maggi, M. Maslov, C. Perez von Thun, S. Scully, N. Vianello, and M. Wischmeier
Subjects: Detachment, Hydrogen isotopes, JET, Nuclear engineering. Atomic power, TK9001-9401
Abstract: Measurements of the ion currents to and plasma conditions at the low-field side (LFS) divertor target plate in low-confinement mode plasmas in the JET ITER-like wall materials configuration show that the core plasma density required to detach the LFS divertor plasma is independent of the hydrogenic species protium, deuterium and tritium, and a 40 %/60 % deuterium–tritium mixture. This observation applies to a divertor plasma configuration with the LFS strike line connected to the horizontal part of the LFS divertor chosen because of its superior diagnostic coverage. The finding is independent of the operational status of the JET cryogenic pump. The electron temperature (Te) at the LFS strike line was markedly reduced from 25 eV to 5 eV over a narrow range of increasing core plasma density, and observed to be between 2 eV and 3 eV at the onset of detachment. The electron density (ne) peaks across the LFS plasma when Te at the target plate is 1 eV, and spatially moves to the X-point for higher core densities. The density limit was found approximately 20 % higher in protium than in tritium and deuterium–tritium plasmas.
Published: 2023
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15. The JET hybrid scenario in Deuterium, Tritium and Deuterium-Tritium

Author: J. Hobirk, C.D. Challis, A. Kappatou, E. Lerche, D. Keeling, D. King, S. Aleiferis, E. Alessi, C. Angioni, F. Auriemma, M. Baruzzo, É. Belonohy, J. Bernardo, A. Boboc, I.S. Carvalho, P. Carvalho, F.J. Casson, A. Chomiczewska, J. Citrin, I.H. Coffey, N.J. Conway, D. Douai, E. Delabie, B. Eriksson, J. Eriksson, O. Ficker, A.R. Field, M. Fontana, J.M. Fontdecaba, L. Frassinetti, D. Frigione, D. Gallart, J. Garcia, M. Gelfusa, Z. Ghani, L. Giacomelli, E. Giovannozzi, C. Giroud, M. Goniche, W. Gromelski, S. Hacquin, C. Ham, N.C. Hawkes, R.B. Henriques, J.C. Hillesheim, A. Ho, L. Horvath, I. Ivanova-Stanik, P. Jacquet, F. Jaulmes, E. Joffrin, H.T. Kim, V. Kiptily, K. Kirov, D. Kos, E. Kowalska-Strzeciwilk, H. Kumpulainen, K. Lawson, M. Lennholm, X. Litaudon, E. Litherland-Smith, P.J. Lomas, E. de la Luna, C.F. Maggi, J. Mailloux, M.J. Mantsinen, M. Maslov, G. Matthews, K.G. McClements, A.G. Meigs, S. Menmuir, A. Milocco, I.G. Miron, S. Moradi, R.B. Morales, S. Nowak, F. Orsitto, A. Patel, L. Piron, C. Prince, G. Pucella, E. Peluso, C. Perez von Thun, E. Rachlew, C. Reux, F. Rimini, S. Saarelma, P. A Schneider, S. Scully, M. Sertoli, S. Sharapov, A. Shaw, S. Silburn, A. Sips, P. Siren, C. Sozzi, E.R. Solano, Z. Stancar, G. Stankunas, C. Stuart, H.J. Sun, G. Szepesi, D. Valcarcel, M. Valisa, G. Verdoolaege, B. Viola, N. Wendler, M. Zerbini, and JET Contributors
Subjects: magnetic fusion, hybrid scenario, Tritium, D-T, isotope effects, Nuclear and particle physics. Atomic energy. Radioactivity, QC770-798
Abstract: The JET hybrid scenario has been developed from low plasma current carbon wall discharges to the record-breaking Deuterium-Tritium plasmas obtained in 2021 with the ITER-like Be/W wall. The development started in pure Deuterium with refinement of the plasma current, and toroidal magnetic field choices and succeeded in solving the heat load challenges arising from 37 MW of injected power in the ITER like wall environment, keeping the radiation in the edge and core controlled, avoiding MHD instabilities and reaching high neutron rates. The Deuterium hybrid plasmas have been re-run in Tritium and methods have been found to keep the radiation controlled but not at high fusion performance probably due to time constraints. For the first time this scenario has been run in Deuterium-Tritium (50:50). These plasmas were re-optimised to have a radiation-stable H-mode entry phase, good impurity control through edge T _i gradient screening and optimised performance with fusion power exceeding 10 MW for longer than three alpha particle slow down times, 8.3 MW averaged over 5 s and fusion energy of 45.8 MJ.
Published: 2023
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16. JET D-T scenario with optimized non-thermal fusion

Author: M. Maslov, E. Lerche, F. Auriemma, E. Belli, C. Bourdelle, C.D. Challis, A. Chomiczewska, A. Dal Molin, J. Eriksson, J. Garcia, J. Hobirk, I. Ivanova-Stanik, Ph. Jacquet, A. Kappatou, Y. Kazakov, D.L. Keeling, D.B. King, V. Kiptily, K. Kirov, D. Kos, R. Lorenzini, E. De La Luna, C.F. Maggi, J. Mailloux, P. Mantica, M. Marin, G. Matthews, I. Monakhov, M. Nocente, G. Pucella, D. Rigamonti, F. Rimini, S. Saarelma, M. Salewski, E.R. Solano, Ž. Štancar, G. Stankunas, H. Sun, M. Tardocchi, D. Van Eester, and JET Contributors
Subjects: tokamak, nuclear fusion, tritium, Nuclear and particle physics. Atomic energy. Radioactivity, QC770-798
Abstract: In JET deuterium-tritium (D-T) plasmas, the fusion power is produced through thermonuclear reactions and reactions between thermal ions and fast particles generated by neutral beam injection (NBI) heating or accelerated by electromagnetic wave heating in the ion cyclotron range of frequencies (ICRFs). To complement the experiments with 50/50 D/T mixtures maximizing thermonuclear reactivity, a scenario with dominant non-thermal reactivity has been developed and successfully demonstrated during the second JET deuterium-tritium campaign DTE2, as it was predicted to generate the highest fusion power in JET with a Be/W wall. It was performed in a 15/85 D/T mixture with pure D-NBI heating combined with ICRF heating at the fundamental deuterium resonance. In steady plasma conditions, a record 59 MJ of fusion energy has been achieved in a single pulse, of which 50.5 MJ were produced in a 5 s time window ( P _fus = 10.1 MW) with average Q = 0.33, confirming predictive modelling in preparation of the experiment. The highest fusion power in these experiments, P _fus = 12.5 MW with average Q = 0.38, was achieved over a shorter 2 s time window, with the period of sustainment limited by high-Z impurity accumulation. This scenario provides unique data for the validation of physics-based models used to predict D-T fusion power.
Published: 2023
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17. Isotope mass scaling and transport comparison between JET Deuterium and Tritium L-mode plasmas

Author: T. Tala, A.E. Järvinen, C.F. Maggi, P. Mantica, A. Mariani, A. Salmi, I.S. Carvalho, A. Chomiczewska, E. Delabie, F. Devasagayam, J. Ferreira, W. Gromelski, N. Hawkes, L. Horvath, J. Karhunen, D. King, A. Kirjasuo, E. Kowalska-Strzeciwilk, S. Leerink, M. Lennholm, B. Lomanowski, M. Maslov, S. Menmuir, R.B. Morales, R. Sharma, H. Sun, K. Tanaka, and JET Contributors
Subjects: isotope mass scaling, Deuterium and Tritium, confinement and transport, JET, dimensionless scaling, heat and particle transport, Nuclear and particle physics. Atomic energy. Radioactivity, QC770-798
Abstract: The dimensionless isotope mass scaling experiment between pure Deuterium and pure Tritium plasmas with matched $\rho^*$ , $\nu^*$ , β _n , q and $T_e/T_i$ has been achieved in JET L-mode with dominant electron heating (NBI+ohmic) conditions. 28% higher scaled energy confinement time $B_t\tau_{E,\mathrm{th}}/A$ is found in favour of the Tritium plasma. This can be cast in the form of the dimensionless energy confinement scaling law as $\Omega_i \tau_{E,\mathrm{th}} \sim A^{0.48 \pm 0.16}$ . This significant isotope mass scaling is consequently seen in the scaled one-fluid heat diffusion coefficient $A \chi_{\mathrm{eff}}/B_t$ which is around 50% lower in the Tritium plasma throughout the whole plasma radius. The isotope mass dependence in the particle transport channel is negligible, supported also by the perturbative particle transport analysis with gas puff modulation. The comparison of the edge particle fuelling or ionisation profiles from the EDGE2D-EIRENE simulations show that the absolute density differences that are necessary for the dimensionless match in the confined plasma dominate over any isotope mass dependencies of particle fuelling and ionization profiles at the plasma edge. Local GENE simulation results indicate a mild anti-gyroBohm effect at $\rho_\mathrm{tor}$ = 0.6 and thereby a small isotope mass dependence in favour of Tritium on heat transport and a negligible effect on particle transport. A significant fraction of the isotope scaling and reduced heat transport observed in the Tritium plasma is not captured in the GENE and ASTRA-TGLF-SAT2 simulations by simply changing the isotope mass for the same input profiles.
Published: 2023
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18. Experiments in high-performance JET plasmas in preparation of second harmonic ICRF heating of tritium in ITER

Author: M.J. Mantsinen, P. Jacquet, E. Lerche, D. Gallart, K. Kirov, P. Mantica, D. Taylor, D. Van Eester, M. Baruzzo, I. Carvalho, C.D. Challis, A. Dal Molin, E. Delabie, E. De La Luna, R. Dumont, P. Dumortier, J. Eriksson, D. Frigione, J. Garcia, L. Garzotti, C. Giroud, R. Henriques, J. Hobirk, A. Kappatou, Y. Kazakov, D. Keeling, D. King, V. Kiptily, M. Lennholm, P. Lomas, C. Lowry, C.F. Maggi, J. Mailloux, M. Maslov, S. Menmuir, I. Monakhov, R.B. Morales, C. Noble, M. Nocente, A. Patel, G. Pucella, C. Reux, D. Rigamonti, F. Rimini, A. Sheikh, S. Silburn, P. Siren, E.R. Solano, Z. Stancar, M. Tardocchi, and JET Contributors
Subjects: ICRF heating, fast ions, computational modelling, JET tokamak, H-mode hybrid plasma scenario, deuterium–tritium fuel mixture, Nuclear and particle physics. Atomic energy. Radioactivity, QC770-798
Abstract: The reference ion cyclotron resonance frequency (ICRF) heating schemes for ITER deuterium–tritium (D-T) plasmas at the full magnetic field of 5.3 T are second harmonic heating of T and ^3 He minority heating. The wave-particle resonance location for these schemes coincide and are central at a wave frequency of 53 MHz at 5.3 T. Experiments have been carried out in the second major D-T campaign (DTE2) at JET, and in its prior D campaigns, to integrate these ICRF scenarios in JET high-performance plasmas and to compare their performance with the commonly used hydrogen (H) minority heating. In 50:50 D:T plasmas, up to 35% and 5% larger fusion power and diamagnetic energy content, respectively, were obtained with second harmonic heating of T as compared to H minority heating at comparable total input powers and gas injection rates. The core ion temperature was up to 30% and 20% higher with second harmonic T and ^3 He minority heating, respectively, with respect to H minority heating. These are favourable results for the use of these scenarios in ITER and future fusion reactors. According to modelling, adding ICRF heating to neutral beam injection using D and T beams resulted in a 10%–20% increase of on-axis bulk ion heating in the D-T plasmas due to its localisation in the plasma core. Central power deposition was confirmed with the break-in-slope and fast Fourier transform analysis of ion and electron temperature in response to ICRF modulation. The tail temperature of fast ICRF-accelerated tritons, their enhancement of the fusion yield and time behaviour as measured by an upgraded magnetic proton recoil spectrometer and neutral particle analyser were found in agreement with theoretical predictions. No losses of ICRF-accelerated ions were observed by fast ion detectors, which was as expected given the high plasma density of n _e ≈ 7–8 × 10 ^19 m ^−3 in the main heating phase that limited the formation of ICRF-accelerated fast ion tails. ^3 He was introduced in the machine by ^3 He gas injection, and the ^3 He concentration was measured by a high-resolution optical penning gauge in the sub-divertor region. The DTE2 experiments with ^3 He minority heating were carried with a low ^3 He concentration in the range of 2%–4% given the fact that the highest neutron rates with ^3 He minority heating in D plasmas were obtained at low ^3 He concentrations of ∼2%, which also coincided with the highest plasma diamagnetic energy content. In addition to ^3 He introduced by ^3 He gas injection, an intrinsic concentration of ^3 He of the order of 0.2%–0.4% was measured in D-T plasmas before ^3 He was introduced in the device, which is attributed to the radioactive decay of tritium to ^3 He. According to modelling, even such low intrinsic concentrations of ^3 He lead to significant changes in ICRF power partitioning during second harmonic heating of T due to absorption of up to 30% of the wave power by ^3 He.
Published: 2023
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19. L-H transition studies in tritium and deuterium–tritium campaigns at JET with Be wall and W divertor

Author: E.R. Solano, G. Birkenmeier, C. Silva, E. Delabie, J.C. Hillesheim, A. Baciero, I. Balboa, M. Baruzzo, A. Boboc, M. Brix, J. Bernardo, C. Bourdelle, I.S. Carvalho, P. Carvalho, C.D. Challis, M. Chernyshova, A. Chomiczewska, R. Coelho, I. Coffey, T. Craciunescu, E. de la Cal, E. de la Luna, R. Dumont, P. Dumortier, M. Fontana, J.M. Fontdecaba, L. Frassinetti, D. Gallart, J. Garcia, C. Giroud, W. Gromelski, R.B. Henriques, J. Hall, A. Ho, L.D. Horton, L. Horvath, P. Jacquet, I. Jepu, E. Joffrin, A. Kappatou, D.L. Keeling, D.B. King, V.G. Kiptily, K.K. Kirov, D. Kos, E. Kowalska-Strzęciwilk, M. Lennholm, E. Lerche, E. Litherland-Smith, A. Loarte, B. Lomanowski, P.J. Lomas, C.F. Maggi, J. Mailloux, M.J. Mantsinen, M. Maslov, A.G. Meigs, I. Monakhov, R.B. Morales, A.H. Nielsen, D. Nina, C. Noble, E. Pawelec, M. Poradzinski, G. Pucella, P. Puglia, D. Réfy, J. Juul Rasmussen, E. Righi, F.G. Rimini, T. Robinson, M. Sertoli, S.A. Silburn, G. Sips, P. Sirén, Ž. Štancar, H.J. Sun, G. Szepesi, D. Taylor, E. Tholerus, B. Thomas, G. Verdoolaege, P. Vincenzi, B. Viola, N. Vianello, T. Wilson, and JET Contributors
Subjects: L-H transition, power threshold, tokamaks, Tritium, DT, JET-ILW, Nuclear and particle physics. Atomic energy. Radioactivity, QC770-798
Abstract: The recent deuterium–tritium campaign in JET-ILW (DTE2) has provided a unique opportunity to study the isotope dependence of the L-H power threshold in an ITER-like wall environment (Be wall and W divertor). Here we present results from dedicated L-H transition experiments at JET-ILW, documenting the power threshold in tritium and deuterium–tritium plasmas, comparing them with the matching deuterium and hydrogen datasets. From earlier experiments in JET-ILW it is known that as plasma isotopic composition changes from deuterium, through varying deuterium/hydrogen concentrations, to pure hydrogen, the value of the line averaged density at which the threshold is minimum, ${\bar n_{{\text{e}},{\text{min}}}}$ , increases, leading us to expect that ${\bar n_{{\text{e}},{\text{min}}}}$ (T) < ${\bar n_{{\text{e}},{\text{min}}}}$ (DT) < ${\bar n_{{\text{e}},{\text{min}}}}$ (D) < ${\bar n_{{\text{e}},{\text{min}}}}$ (H). The new power threshold data confirms these expectations in most cases, with the corresponding ordering of the minimum power thresholds. We present a comparison of this data to power threshold scalings, used for extrapolation to future devices such as ITER and DEMO.
Published: 2023
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20. Tritium removal from JET-ILW after T and D–T experimental campaigns

Author: D. Matveev, D. Douai, T. Wauters, A. Widdowson, I. Jepu, M. Maslov, S. Brezinsek, T. Dittmar, I. Monakhov, P. Jacquet, P. Dumortier, H. Sheikh, R. Felton, C. Lowry, D. Ciric, J. Banks, R. Buckingham, H. Weisen, L. Laguardia, G. Gervasini, E. de la Cal, E. Delabie, Z. Ghani, J. Gaspar, J. Romazanov, M. Groth, H. Kumpulainen, J. Karhunen, S. Knipe, S. Aleiferis, T. Loarer, A. Meigs, C. Noble, G. Papadopoulos, E. Pawelec, S. Romanelli, S. Silburn, E. Joffrin, E. Tsitrone, F. Rimini, C.F. Maggi, and JET Contributors
Subjects: JET-ILW, tritium retention, tritium removal, wall cleaning, DTE2, Nuclear and particle physics. Atomic energy. Radioactivity, QC770-798
Abstract: After the second Deuterium–Tritium Campaign (DTE2) in the JET tokamak with the ITER-Like Wall (ILW) and full tritium campaigns that preceded and followed after the DTE2, a sequence of fuel recovery methods was applied to promote tritium removal from wall components. The sequence started with several days of baking of the main chamber walls at 240 °C and at 320 °C. Subsequently, baking was superimposed with Ion-Cyclotron Wall Conditioning (ICWC) and Glow Discharge Conditioning (GDC) cleaning cycles in deuterium. Diverted plasma operation in deuterium with different strike point configurations, including a Raised Inner Strike Point (RISP) configuration, and with different plasma heating—Ion Cyclotron Resonance Frequency (ICRF) and Neutral Beam Injection (NBI)—concluded the cleaning sequence. Tritium content in plasma and in the pumped gas was monitored throughout the experiment. The applied fuel recovery methods allowed reducing the residual tritium content in deuterium NBI-heated plasmas to about 0.1% as deduced from neutron rate measurements. This value is well below the requirement of 1% set by the maximum 14 MeV fusion neutron budget allocated in the ensuing deuterium plasma campaign. The quantified tritium removal over the course of the experiment was $\left( {13.4 \pm 0.7} \right) \times {10^{22}}$ atoms or $\left( {0.67 \pm 0.03} \right)$ g with ∼58% attributed to baking, ∼12.5% to ICWC, ∼26% to GDC, and ∼3.5% to first low power RISP plasmas. The experimentally estimated amount of removed tritium is in good agreement with long-term tritium accounting by the JET tritium reprocessing plant, in which the unaccounted amount was reduced by $0.71$ g after the cleaning experiment.
Published: 2023
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21. Isotope physics of heat and particle transport with tritium in JET-ILW type-I ELMy H-mode plasmas

Author: P.A. Schneider, C. Angioni, F. Auriemma, N. Bonanomi, T. Görler, R. Henriques, L. Horvath, D. King, R. Lorenzini, H. Nyström, M. Maslov, J. Ruiz, G. Szepesi, C.D. Challis, A. Chomiczewska, E. Delabie, J.M. Fontdecaba, L. Frassinetti, J. Garcia, C. Giroud, J. Hillesheim, J. Hobirk, A. Kappatou, D.L. Keeling, E. Kowalska-Strzeciwilk, M. Lennholm, B. Lomanowski, T. Luda di Cortemiglia, C.F. Maggi, S. Menmuir, G. Pucella, A. Thorman, and JET Contributors
Subjects: H-mode, tritium, heat transport, particle transport, stability, isotopes, Nuclear and particle physics. Atomic energy. Radioactivity, QC770-798
Abstract: As part the DTE2 campaign in the JET tokamak, we conducted a parameter scan in T and D-T complementing existing pulses in H and D. For the different main ion masses, type-I ELMy H-modes at fixed plasma current and magnetic field can have the pedestal pressure varying by a factor of 4 and the total pressure changing from $\beta_{\mathrm{N}} = 1.0$ to 3.0. We investigated the pedestal and core isotope mass dependencies using this extensive data set. The pedestal shows a strong mass dependence on the density, which influences the core due to the strong coupling between both plasma regions. To better understand the causes for the observed isotope mass dependence in the pedestal, we analysed the interplay between heat and particle transport and the edge localised mode (ELM) stability. For this purpose, we developed a dynamic ELM cycle model with basic transport assumptions and a realistic neutral penetration. The temporal evolution and resulting ELM frequency introduce an additional experimental constraint that conventional quasi-stationary transport analysis cannot provide. Our model shows that a mass dependence in the ELM stability or in the transport alone cannot explain the observations. One requires a mass dependence in the ELM stability as well as one in the particle sources. The core confinement time increases with pedestal pressure for all isotope masses due to profile stiffness and electromagnetic turbulence stabilisation. Interestingly, T and D-T plasmas show an improved core confinement time compared to H and D plasmas even for matched pedestal pressures. For T, this improvement is largely due to the unique pedestal composition of higher densities and lower temperatures than H and D. With a reduced gyroBohm factor at lower temperatures, more turbulent drive in the form of steeper gradients is required to transport the same amount of heat. This picture is supported by quasilinear flux-driven modelling using TGLF -SAT2 within Astra . With the experimental boundary condition TGLF -SAT2 predicts the core profiles well for gyroBohm heat fluxes ${\gt}15$ , however, overestimates the heat and particle transport closer to the turbulent threshold.
Published: 2023
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22. Overview of interpretive modelling of fusion performance in JET DTE2 discharges with TRANSP

Author: Ž. Štancar, K.K. Kirov, F. Auriemma, H.-T. Kim, M. Poradziński, R. Sharma, R. Lorenzini, Z. Ghani, M. Gorelenkova, F. Poli, A. Boboc, S. Brezinsek, P. Carvalho, F.J. Casson, C.D. Challis, E. Delabie, D. Van Eester, M. Fitzgerald, J.M. Fontdecaba, D. Gallart, J. Garcia, L. Garzotti, C. Giroud, A. Kappatou, Ye.O. Kazakov, D.B. King, V.G. Kiptily, D. Kos, E. Lerche, E. Litherland-Smith, C.F. Maggi, P. Mantica, M.J. Mantsinen, M. Maslov, S. Menmuir, M. Nocente, H.J.C. Oliver, S.E. Sharapov, P. Sirén, E.R. Solano, H.J. Sun, G. Szepesi, and JET Contributors
Subjects: deuterium-tritium plasma, integrated modelling, fusion performance, JET, TRANSP, Nuclear and particle physics. Atomic energy. Radioactivity, QC770-798
Abstract: In the paper we present an overview of interpretive modelling of a database of JET-ILW 2021 D-T discharges using the TRANSP code. The main aim is to assess our capability of computationally reproducing the fusion performance of various D-T plasma scenarios using different external heating and D-T mixtures, and to understand the performance driving mechanisms. We find that interpretive simulations confirm a general power-law relationship between increasing external heating power and fusion output, which is supported by absolutely calibrated neutron yield measurements. A comparison of measured and computed D-T neutron rates shows that the calculations’ discrepancy depends on the absolute neutron yield. The calculations are found to agree well with measurements for higher performing discharges with external heating power above ∼20 $\mathrm{MW}$ , while low-neutron shots display an average discrepancy of around +40% compared to measured neutron yields. A similar trend is found for the ratio between thermal and beam-target fusion, where larger discrepancies are seen in shots with dominant beam-driven performance. We compare the observations to studies of JET-ILW D discharges, to find that on average the fusion performance is well modelled over a range of heating power, although an increased unsystematic deviation for lower-performing shots is observed. The ratio between thermal and beam-induced D-T fusion is found to be increasing weakly with growing external heating power, with a maximum value of $\gtrsim$ 1 achieved in a baseline scenario experiment. An evaluation of the fusion power computational uncertainty shows a strong dependence on the plasma scenario type and fusion drive characteristics, varying between ±25% and 35%. D-T fusion alpha simulations show that the ratio between volume-integrated electron and ion heating from alphas is $\lesssim$ 10 for the majority of analysed discharges. Alphas are computed to contribute between ∼15% and 40% to the total electron heating in the core of highest performing D-T discharges. An alternative workflow to TRANSP was employed to model JET D-T plasmas with the highest fusion yield and dominant non-thermal fusion component because of the use of fundamental radio-frequency heating of a large minority in the scenario, which is calculated to have provided ∼10% to the total fusion power.
Published: 2023
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23. Impact of interaction between RF waves and fast NBI ions on the fusion performance in JET DTE2 campaign

Author: K.K. Kirov, C.D. Challis, E. De la Luna, J. Eriksson, D. Gallart, J. Garcia, M. Gorelenkova, J. Hobirk, P. Jacquet, A. Kappatou, Y.O. Kazakov, D. Keeling, D. King, E. Lerche, C. Maggi, J. Mailloux, P. Mantica, M. Mantsinen, M. Maslov, S. Menmuir, P. Siren, Z. Stancar, D. Van Eester, and JET Contributors
Subjects: RF waves, fast ions, DT plasma, JET, fusion performance, Nuclear and particle physics. Atomic energy. Radioactivity, QC770-798
Abstract: This work presents a study of the interaction between radio frequency (RF) waves used for ion cyclotron resonance heating and the fast deuterium (D) and tritium (T) neutral Beam injected (NBI) ions in DT plasma. The focus is on the effects of this interaction, also referred to as synergistic effects, on the fusion performance in the recent JET DTE2 campaign. Experimental data from dedicated pulses at 3.43 T/2.3 MA heated at (i) 51.4 MHz, giving the central minority H and n = 2 D, and at (ii) 32.2 MHz for the central minority ^3 He and n = 2 T. Resonances are analysed and conclusions are drawn and supported by modelling of the synergistic effects. Modelling with transport code TRANSP runs with and without the RF kick operator predict a moderate increase, of about 10%, in DT rates for the case of the RF wave—fast D NBI ion interactions at the n = 2 harmonic of ion cyclotron resonance, and a negligible impact due to synergistic interaction between fast T NBI ions and RF waves. JETTO modelling gives a 29% enhancement in fusion rates due to the interction between RF waves and fast D NBI ions, and an 18% enhancement in fast T NBI ions. Analysis of experimental neutron rates compared to TRANSP predictions without synergistic effects and magnetic proton recoil neutron spectrometer indicate an enhancement of approximately 25%–28% in fusion rates due to RF interaction with fast D ions, and an enhancement of approximately 5%–8% when RF waves and fast T NBI ions are interacting. The contributions of various heating and fast ion sources are assessed and discussed.
Published: 2023
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24. Parameter dependencies of the separatrix density in low triangularity L-mode and H-mode JET-ILW plasmas

Author: B. Lomanowski, G. Rubino, A. Uccello, M. Dunne, N. Vianello, S. Aleiferis, J. Canik, I. Carvalho, G. Corrigan, L. Frassinetti, D. Frigione, L. Garzotti, M. Groth, A. Meigs, M. Maslov, C. Perez von Thun, F. Rimini, P.A. Schneider, G. Sergienko, J. Simpson, D. Van Eester, and JET Contributors
Subjects: separatrix density, divertor and main chamber recycling, two point model, SOL-pedestal-core integration, Nuclear and particle physics. Atomic energy. Radioactivity, QC770-798
Abstract: The midplane electron separatrix density, n _e,sep , in JET-ILW L-mode and H-mode low triangularity deuterium fuelled plasmas exhibits a strong explicit dependence on the averaged outer divertor target electron temperature, n _e,sep ∼ T _e,ot ^−1/2 . This dependence is reproduced by analytic reversed two point model (rev-2PM), and arises from parallel pressure balance, as well as the ratio of the power and momentum volumetric loss factors, (1 − f _cooling )/(1 − f _mom-loss ). Quantifying the influence of the (1 − f _cooling ) and (1 − f _mom-loss ) loss factors on n _e,sep has been enabled by measurement estimates of these quantities from L-mode density (fueling) ramps in the outer horizontal, VH(C), and vertical target, VV, divertor configurations. Rev-2PM n _e,sep estimates from the extended H-mode and more limited L-mode datasets are recovered to within ±25% of the measurements, with a scaling factor applied to account for use of $\left\langle {{T_{{\text{e,ot}}}}} \right\rangle $ , an averaged quantity, rather than flux tube resolved target values. Both the (1 − f _cooling ) and (1 − f _mom-loss ) trends and recovery of n _e,sep using the rev-2PM formatting are reproduced in EDGE2D-EIRENE L-mode-like and H-mode-like density scan simulations. The general lack of a divertor configuration effect in the JET-ILW n _e,sep trends can be attributed to a significant influence of main chamber recycling, which has been shown in the EDGE2D-EIRENE results to moderate n _e,sep with respect to changes in divertor neutral leakage imposed by changes in the divertor configuration. The unified n _e,sep vs $\left\langle {{T_{{\text{e,ot}}}}} \right\rangle $ trends can, however, be broken if large modifications to the divertor geometry (e.g. complete removal of the outer divertor baffle structure) are introduced in the model. The more pronounced high-field side high density region formation in the VH(C) configuration with reduced clearance to the separatrix does not appear to have a significant influence on the outer midplane separatrix and pedestal parameters when mapped to $\left\langle {{T_{{\text{e,ot}}}}} \right\rangle $ , although conditions at the inner midplane could not be assessed.
Published: 2023
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25. The broadening of SOL profiles in JET tritium plasma and its impact on machine operation

Author: H.J. Sun, S.A. Silburn, I.S. Carvalho, D.B. King, C. Giroud, G. Fishpool, G.F. Matthews, R.B. Henriques, D.L. Keeling, F.G. Rimini, L. Garzotti, D. Frigione, D. Van Eester, M. Groth, J. Flanagan, D. Kos, B. Viola, A. Boboc, P. Shi, M.-L. Mayoral, J. Mailloux, C. Maggi, A. Huber, D. Douai, N. Vianello, P.J. Lomas, M. Lennholm, M. Maslov, K. Kirov, P. Jacquet, C.G. Lowry, M. Baruzzo, C. Stuart, J. Mitchell, L. Horvath, D.C. McDonald, and JET Contributors
Subjects: JET tokamak, SOL broadening, density shoulder formation, power exhaust, plasma wall interaction, Nuclear and particle physics. Atomic energy. Radioactivity, QC770-798
Abstract: Unusually high power loads on the beryllium limiter caused by neutral beam re-ionisation, and much cooler divertor target surfaces were observed during the recent JET tokamak tritium campaign. As both phenomena are driven by scrape-off layer (SOL) physics, the SOL features of 72 tritium H-mode discharges and their deuterium references have been studied. The majority (70) of tritium H-mode discharges had exponentially decaying SOL profiles. The tritium plasmas are observed to have increased separatrix density and collisionality compared to their deuterium references. This is associated with $ \approx 2 - 3$ times broader SOL width for both density and temperature profiles. This is consistent with previous observations in highly collisional deuterium H-mode plasma on the ASDEX Upgrade tokamak (Sun et al 2015 Plasma Phys. Control. Fusion 57 125011) and interpreted as high collisionality enhancing cross-field transport across the separatrix and resulting in the broadening of near SOL above a critical value. The other two tritium H-mode discharges had near flat SOL density profiles, similar to the so-called ‘ density shoulder formation ’ observed in L-mode plasma. The SOL collisionality of these two pulses lies within the range of T pulses without density shoulder formation. This supports the conclusion of previous studies (Vianello et al 2017 Nucl. Fusion 57 116014; Wynn et al 2018 Nucl. Fusion 58 056001) that increased collisionality is not sufficient for the formation of a ‘ density shoulder ’ and additional factors, likely divertor condition or interaction with neutrals, are required. JET tritium plasma provides evidence of favourable and unfavourable effects of enhanced cross-field SOL transport on machine operation. The larger limiter power loads due to re-ionisation of neutral beam injection observed in the T pulses relative to their D references has been shown to be consistent with the combined effects of the broadening of the SOL profile and larger beam ion Larmor radius. The enhanced cross-field particle transport and the resulting broader SOL width provides more particles to ionize the fast Beam neutrals, causing the unfavourable power load issue on the beryllium limiter. The broader near SOL profiles of the T plasma spreads the heat load over a larger area and, together with the increased separatrix density, results in a favourably cooler divertor target surface.
Published: 2022
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26. Global scaling of the heat transport in fusion plasmas

Author: Sara Moradi, Johan Anderson, Michele Romanelli, Hyun-Tae Kim, JET contributors, X. Litaudon, S. Abduallev, M. Abhangi, P. Abreu, M. Afzal, K. M. Aggarwal, T. Ahlgren, J. H. Ahn, L. Aho-Mantila, N. Aiba, M. Airila, R. Albanese, V. Aldred, D. Alegre, E. Alessi, P. Aleynikov, A. Alfier, A. Alkseev, M. Allinson, B. Alper, E. Alves, G. Ambrosino, R. Ambrosino, L. Amicucci, V. Amosov, E. Andersson Sundén, M. Angelone, M. Anghel, C. Angioni, L. Appel, C. Appelbee, P. Arena, M. Ariola, H. Arnichand, S. Arshad, A. Ash, N. Ashikawa, V. Aslanyan, O. Asunta, F. Auriemma, Y. Austin, L. Avotina, M. D. Axton, C. Ayres, M. Bacharis, A. Baciero, D. Baião, S. Bailey, A. Baker, I. Balboa, M. Balden, N. Balshaw, R. Bament, J. W. Banks, Y. F. Baranov, M. A. Barnard, D. Barnes, M. Barnes, R. Barnsley, A. Baron Wiechec, L. Barrera Orte, M. Baruzzo, V. Basiuk, M. Bassan, R. Bastow, A. Batista, P. Batistoni, R. Baughan, B. Bauvir, L. Baylor, B. Bazylev, J. Beal, P. S. Beaumont, M. Beckers, B. Beckett, A. Becoulet, N. Bekris, M. Beldishevski, K. Bell, F. Belli, M. Bellinger, É. Belonohy, N. Ben Ayed, N. A. Benterman, H. Bergsȧker, J. Bernardo, M. Bernert, M. Berry, L. Bertalot, C. Besliu, M. Beurskens, B. Bieg, J. Bielecki, T. Biewer, M. Bigi, P. Bìlkovà, F. Binda, A. Bisoffi, J. P. S. Bizarro, C. Björkas, J. Blackburn, K. Blackman, T. R. Blackman, P. Blanchard, P. Blatchford, V. Bobkov, A. Boboc, G. Bodnàr, O. Bogar, I. Bolshakova, T. Bolzonella, N. Bonanomi, F. Bonelli, J. Boom, J. Booth, D. Borba, D. Borodin, I. Borodkina, A. Botrugno, C. Bottereau, P. Boulting, C. Bourdelle, M. Bowden, C. Bower, C. Bowman, T. Boyce, C. Boyd, H. J. Boyer, J. M. A. Bradshaw, V. Braic, R. Bravanec, B. Breizman, S. Bremond, P. D. Brennan, S. Breton, A. Brett, S. Brezinsek, M. D. J. Bright, M. Brix, W. Broeckx, M. Brombin, A. Brosawski, D. P. D. Brown, M. Brown, E. Bruno, J. Bucalossi, J. Buch, J. Buchanan, M. A. Buckley, R. Budny, H. Bufferand, M. Bulman, N. Bulmer, P. Bunting, P. Buratti, A. Burckhart, A. Buscarino, A. Busse, N. K. Butler, I. Bykov, J. Byrne, P. Cahyna, G. Calabrò, I. Calvo, Y. Camenen, P. Camp, D. C. Campling, J. Cane, B. Cannas, A. J. Capel, P. J. Card, A. Cardinali, P. Carman, M. Carr, D. Carralero, L. Carraro, B. B. Carvalho, I. Carvalho, P. Carvalho, F. J. Casson, C. Castaldo, N. Catarino, J. Caumont, F. Causa, R. Cavazzana, K. Cave-Ayland, M. Cavinato, M. Cecconello, S. Ceccuzzi, E. Cecil, A. Cenedese, R. Cesario, C. D. Challis, M. Chandler, D. Chandra, C. S. Chang, A. Chankin, I. T. Chapman, S. C. Chapman, M. Chernyshova, G. Chitarin, G. Ciraolo, D. Ciric, J. Citrin, F. Clairet, E. Clark, M. Clark, R. Clarkson, D. Clatworthy, C. Clements, M. Cleverly, J. P. Coad, P. A. Coates, A. Cobalt, V. Coccorese, V. Cocilovo, S. Coda, R. Coelho, J. W. Coenen, I. Coffey, L. Colas, S. Collins, D. Conka, S. Conroy, N. Conway, D. Coombs, D. Cooper, S. R. Cooper, C. Corradino, Y. Corre, G. Corrigan, S. Cortes, D. Coster, A. S. Couchman, M. P. Cox, T. Craciunescu, S. Cramp, R. Craven, F. Crisanti, G. Croci, D. Croft, K. Crombé, R. Crowe, N. Cruz, G. Cseh, A. Cufar, A. Cullen, M. Curuia, A. Czarnecka, H. Dabirikhah, P. Dalgliesh, S. Dalley, J. Dankowski, D. Darrow, O. Davies, W. Davis, C. Day, I. E. Day, M. De Bock, A. de Castro, E. de la Cal, E. de la Luna, G. De Masi, J. L. de Pablos, G. De Temmerman, G. De Tommasi, P. de Vries, K. Deakin, J. Deane, F. Degli Agostini, R. Dejarnac, E. Delabie, N. den Harder, R. O. Dendy, J. Denis, P. Denner, S. Devaux, P. Devynck, F. Di Maio, A. Di Siena, C. Di Troia, P. Dinca, R. Dinca, B. Ding, T. Dittmar, H. Doerk, R. P. Doerner, T. Donné, S. E. Dorling, S. Dormido-Canto, S. Doswon, D. Douai, P. T. Doyle, A. Drenik, P. Drewelow, P. Drews, Ph. Duckworth, R. Dumont, P. Dumortier, D. Dunai, M. Dunne, I. Duran, F. Durodié, P. Dutta, B. P. Duval, R. Dux, K. Dylst, N. Dzysiuk, P. V. Edappala, J. Edmond, A. M. Edwards, J. Edwards, Th. Eich, A. Ekedahl, R. El-Jorf, C. G. Elsmore, M. Enachescu, G. Ericsson, F. Eriksson, J. Eriksson, L. G. Eriksson, B. Esposito, S. Esquembri, H. G. Esser, D. Esteve, B. Evans, G. E. Evans, G. Evison, G. D. Ewart, D. Fagan, M. Faitsch, D. Falie, A. Fanni, A. Fasoli, J. M. Faustin, N. Fawlk, L. Fazendeiro, N. Fedorczak, R. C. Felton, K. Fenton, A. Fernades, H. Fernandes, J. Ferreira, J. A. Fessey, O. Février, O. Ficker, A. Field, S. Fietz, A. Figueiredo, J. Figueiredo, A. Fil, P. Finburg, M. Firdaouss, U. Fischer, L. Fittill, M. Fitzgerald, D. Flammini, J. Flanagan, C. Fleming, K. Flinders, N. Fonnesu, J. M. Fontdecaba, A. Formisano, L. Forsythe, L. Fortuna, E. Fortuna-Zalesna, M. Fortune, S. Foster, T. Franke, T. Franklin, M. Frasca, L. Frassinetti, M. Freisinger, R. Fresa, D. Frigione, V. Fuchs, D. Fuller, S. Futatani, J. Fyvie, K. Gàl, D. Galassi, K. Galazka, J. Galdon-Quiroga, J. Gallagher, D. Gallart, R. Galvão, X. Gao, Y. Gao, J. Garcia, A. Garcia-Carrasco, M. Garca-Munoz, J.-L. Gardarein, L. Garzotti, P. Gaudio, E. Gauthier, D. F. Gear, S. J. Gee, B. Geiger, M. Gelfusa, S. Gerasimov, G. Gervasini, M. Gethins, Z. Ghani, M. Ghate, M. Gherendi, J. C. Giacalone, L. Giacomelli, C. S. Gibson, T. Giegerich, C. Gil, L. Gil, S. Gilligan, D. Gin, E. Giovannozzi, J. B. Girardo, C. Giroud, G. Giruzzi, S. Glöggler, J. Godwin, J. Goff, P. Gohil, V. Goloborod'ko, R. Gomes, B. Goncalves, M. Goniche, M. Goodliffe, A. Goodyear, G. Gorini, M. Gosk, R. Goulding, A. Goussarov, R. Gowland, B. Graham, M. E. Graham, J. P. Graves, N. Grazier, P. Grazier, N. R. Green, H. Greuner, B. Grierson, F. S. Griph, C. Grisolia, D. Grist, M. Groth, R. Grove, C. N. Grundy, J. Grzonka, D. Guard, C. Guérard, C. Guillemaut, R. Guirlet, C. Gurl, H. H. Utoh, L. J. Hackett, S. Hacquin, A. Hagar, R. Hager, A. Hakola, M. Halitovs, S. J. Hall, S. P. Hallworth Cook, C. Hamlyn-Harris, K. Hammond, C. Harrington, J. Harrison, D. Harting, F. Hasenbeck, Y. Hatano, D. R. Hatch, T. D. V. Haupt, J. Hawes, N. C. Hawkes, J. Hawkins, P. Hawkins, P. W. Haydon, N. Hayter, S. Hazel, P. J. L. Heesterman, K. Heinola, C. Hellesen, T. Hellsten, W. Helou, O. N. Hemming, T. C. Hender, M. Henderson, S. S. Henderson, R. Henriques, D. Hepple, G. Hermon, P. Hertout, C. Hidalgo, E. G. Highcock, M. Hill, J. Hillairet, J. Hillesheim, D. Hillis, K. Hizanidis, A. Hjalmarsson, J. Hobirk, E. Hodille, C. H. A. Hogben, G. M. D. Hogeweij, A. Hollingsworth, S. Hollis, D. A. Homfray, J. Horàcek, G. Hornung, A. R. Horton, L. D. Horton, L. Horvath, S. P. Hotchin, M. R. Hough, P. J. Howarth, A. Hubbard, A. Huber, V. Huber, T. M. Huddleston, M. Hughes, G. T. A. Huijsmans, C. L. Hunter, P. Huynh, A. M. Hynes, D. Iglesias, N. Imazawa, F. Imbeaux, M. Imrìŝek, M. Incelli, P. Innocente, M. Irishkin, I. Ivanova-Stanik, S. Jachmich, A. S. Jacobsen, P. Jacquet, J. Jansons, A. Jardin, A. Järvinen, F. Jaulmes, S. Jednoróq, I. Jenkins, C. Jeong, I. Jepu, E. Joffrin, R. Johnson, T. Johnson, Jane Johnston, L. Joita, G. Jones, T. T. C. Jones, K. K. Hoshino, A. Kallenbach, K. Kamiya, J. Kaniewski, A. Kantor, A. Kappatou, J. Karhunen, D. Karkinsky, I. Karnowska, M. Kaufman, G. Kaveney, Y. Kazakov, V. Kazantzidis, D. L. Keeling, T. Keenan, J. Keep, M. Kempenaars, C. Kennedy, D. Kenny, J. Kent, O. N. Kent, E. Khilkevich, H. T. Kim, H. S. Kim, A. Kinch, C. King, D. King, R. F. King, D. J. Kinna, V. Kiptily, A. Kirk, K. Kirov, A. Kirschner, G. Kizane, C. Klepper, A. Klix, P. Knight, S. J. Knipe, S. Knott, T. Kobuchi, F. Köchl, G. Kocsis, I. Kodeli, L. Kogan, D. Kogut, S. Koivuranta, Y. Kominis, M. Köppen, B. Kos, T. Koskela, H. R. Koslowski, M. Koubiti, M. Kovari, E. Kowalska-Strzeciwilk, A. Krasilnikov, V. Krasilnikov, N. Krawczyk, M. Kresina, K. Krieger, A. Krivska, U. Kruezi, I. Ksiazek, A. Kukushkin, A. Kundu, T. Kurki-Suonio, S. Kwak, R. Kwiatkowski, O. J. Kwon, L. Laguardia, A. Lahtinen, A. Laing, N. Lam, H. T. Lambertz, C. Lane, P. T. Lang, S. Lanthaler, J. Lapins, A. Lasa, J. R. Last, E. Laszynska, R. Lawless, A. Lawson, K. D. Lawson, A. Lazaros, E. Lazzaro, J. Leddy, S. Lee, X. Lefebvre, H. J. Leggate, J. Lehmann, M. Lehnen, D. Leichtle, P. Leichuer, F. Leipold, I. Lengar, M. Lennholm, E. Lerche, A. Lescinskis, S. Lesnoj, E. Letellier, M. Leyland, W. Leysen, L. Li, Y. Liang, J. Likonen, J. Linke, Ch. Linsmeier, B. Lipschultz, G. Liu, Y. Liu, V. P. Lo Schiavo, T. Loarer, A. Loarte, R. C. Lobel, B. Lomanowski, P. J. Lomas, J. Lönnroth, J. M. López, J. López-Razola, R. Lorenzini, U. Losada, J. J. Lovell, A. B. Loving, C. Lowry, T. Luce, R. M. A. Lucock, A. Lukin, C. Luna, M. Lungaroni, C. P. Lungu, M. Lungu, A. Lunniss, I. Lupelli, A. Lyssoivan, N. Macdonald, P. Macheta, K. Maczewa, B. Magesh, P. Maget, C. Maggi, H. Maier, J. Mailloux, T. Makkonen, R. Makwana, A. Malaquias, A. Malizia, P. Manas, A. Manning, M. E. Manso, P. Mantica, M. Mantsinen, A. Manzanares, Ph. Maquet, Y. Marandet, N. Marcenko, C. Marchetto, O. Marchuk, M. Marinelli, M. Marinucci, T. Markovic, D. Marocco, L. Marot, C. A. Marren, R. Marshal, A. Martin, Y. Martin, A. Martín de Aguilera, F. J. Martínez, J. R. Martín-Solís, Y. Martynova, S. Maruyama, A. Masiello, M. Maslov, S. Matejcik, M. Mattei, G. F. Matthews, F. Maviglia, M. Mayer, M. L. Mayoral, T. May-Smith, D. Mazon, C. Mazzotta, R. McAdams, P. J. McCarthy, K. G. McClements, O. McCormack, P. A. McCullen, D. McDonald, S. McIntosh, R. McKean, J. McKehon, R. C. Meadows, A. Meakins, F. Medina, M. Medland, S. Medley, S. Meigh, A. G. Meigs, G. Meisl, S. Meitner, L. Meneses, S. Menmuir, K. Mergia, I. R. Merrigan, Ph. Mertens, S. Meshchaninov, A. Messiaen, H. Meyer, S. Mianowski, R. Michling, D. Middleton-Gear, J. Miettunen, F. Militello, E. Militello-Asp, G. Miloshevsky, F. Mink, S. Minucci, Y. Miyoshi, J. Mlynàr, D. Molina, I. Monakhov, M. Moneti, R. Mooney, S. Moradi, S. Mordijck, L. Moreira, R. Moreno, F. Moro, A. W. Morris, J. Morris, L. Moser, S. Mosher, D. Moulton, A. Murari, A. Muraro, S. Murphy, N. N. Asakura, Y. S. Na, F. Nabais, R. Naish, T. Nakano, E. Nardon, V. Naulin, M. F. F. Nave, I. Nedzelski, G. Nemtsev, F. Nespoli, A. Neto, R. Neu, V. S. Neverov, M. Newman, K. J. Nicholls, T. Nicolas, A. H. Nielsen, P. Nielsen, E. Nilsson, D. Nishijima, C. Noble, M. Nocente, D. Nodwell, K. Nordlund, H. Nordman, R. Nouailletas, I. Nunes, M. Oberkofler, T. Odupitan, M. T. Ogawa, T. O'Gorman, M. Okabayashi, R. Olney, O. Omolayo, M. O'Mullane, J. Ongena, F. Orsitto, J. Orszagh, B. I. Oswuigwe, R. Otin, A. Owen, R. Paccagnella, N. Pace, D. Pacella, L. W. Packer, A. Page, E. Pajuste, S. Palazzo, S. Pamela, S. Panja, P. Papp, R. Paprok, V. Parail, M. Park, F. Parra Diaz, M. Parsons, R. Pasqualotto, A. Patel, S. Pathak, D. Paton, H. Patten, A. Pau, E. Pawelec, C. Paz Soldan, A. Peackoc, I. J. Pearson, S.-P. Pehkonen, E. Peluso, C. Penot, A. Pereira, R. Pereira, P. P. Pereira Puglia, C. Perez von Thun, S. Peruzzo, S. Peschanyi, M. Peterka, P. Petersson, G. Petravich, A. Petre, N. Petrella, V. Petrzilka, Y. Peysson, D. Pfefferlé, V. Philipps, M. Pillon, G. Pintsuk, P. Piovesan, A. Pires dos Reis, L. Piron, A. Pironti, F. Pisano, R. Pitts, F. Pizzo, V. Plyusnin, N. Pomaro, O. G. Pompilian, P. J. Pool, S. Popovichev, M. T. Porfiri, C. Porosnicu, M. Porton, G. Possnert, S. Potzel, T. Powell, J. Pozzi, V. Prajapati, R. Prakash, G. Prestopino, D. Price, M. Price, R. Price, P. Prior, R. Proudfoot, G. Pucella, P. Puglia, M. E. Puiatti, D. Pulley, K. Purahoo, Th. Pütterich, E. Rachlew, M. Rack, R. Ragona, M. S. J. Rainford, A. Rakha, G. Ramogida, S. Ranjan, C. J. Rapson, J. J. Rasmussen, K. Rathod, G. Rattà, S. Ratynskaia, G. Ravera, C. Rayner, M. Rebai, D. Reece, A. Reed, D. Réfy, B. Regan, J. Regana, M. Reich, N. Reid, F. Reimold, M. Reinhart, M. Reinke, D. Reiser, D. Rendell, C. Reux, S. D. A. Reyes Cortes, S. Reynolds, V. Riccardo, N. Richardson, K. Riddle, D. Rigamonti, F. G. Rimini, J. Risner, M. Riva, C. Roach, R. J. Robins, S. A. Robinson, T. Robinson, D. W. Robson, R. Roccella, R. Rodionov, P. Rodrigues, J. Rodriguez, V. Rohde, F. Romanelli, M. Romanelli, S. Romanelli, J. Romazanov, S. Rowe, M. Rubel, G. Rubinacci, G. Rubino, L. Ruchko, M. Ruiz, C. Ruset, J. Rzadkiewicz, S. Saarelma, R. Sabot, E. Safi, P. Sagar, G. Saibene, F. Saint-Laurent, M. Salewski, A. Salmi, R. Salmon, F. Salzedas, D. Samaddar, U. Samm, D. Sandiford, P. Santa, M. I. K. Santala, B. Santos, A. Santucci, F. Sartori, R. Sartori, O. Sauter, R. Scannell, T. Schlummer, K. Schmid, V. Schmidt, S. Schmuck, M. Schneider, K. Schöpf, D. Schwörer, S. D. Scott, G. Sergienko, M. Sertoli, A. Shabbir, S. E. Sharapov, A. Shaw, R. Shaw, H. Sheikh, A. Shepherd, A. Shevelev, A. Shumack, G. Sias, M. Sibbald, B. Sieglin, S. Silburn, A. Silva, C. Silva, P. A. Simmons, J. Simpson, J. Simpson-Hutchinson, A. Sinha, S. K. Sipilä, A. C. C. Sips, P. Sirén, A. Sirinelli, H. Sjöstrand, M. Skiba, R. Skilton, K. Slabkowska, B. Slade, N. Smith, P. G. Smith, R. Smith, T. J. Smith, M. Smithies, L. Snoj, S. Soare, E. R. Solano, A. Somers, C. Sommariva, P. Sonato, A. Sopplesa, J. Sousa, C. Sozzi, S. Spagnolo, T. Spelzini, F. Spineanu, G. Stables, I. Stamatelatos, M. F. Stamp, P. Staniec, G. Stankunas, C. Stan-Sion, M. J. Stead, E. Stefanikova, I. Stepanov, A. V. Stephen, M. Stephen, A. Stevens, B. D. Stevens, J. Strachan, P. Strand, H. R. Strauss, P. Ström, G. Stubbs, W. Studholme, F. Subba, H. P. Summers, J. Svensson, L. Swiderski, T. Szabolics, M. Szawlowski, G. Szepesi, T. T. Suzuki, B. Tàl, T. Tala, A. R. Talbot, S. Talebzadeh, C. Taliercio, P. Tamain, C. Tame, W. Tang, M. Tardocchi, L. Taroni, D. Taylor, K. A. Taylor, D. Tegnered, G. Telesca, N. Teplova, D. Terranova, D. Testa, E. Tholerus, J. Thomas, J. D. Thomas, P. Thomas, A. Thompson, C.-A. Thompson, V. K. Thompson, L. Thorne, A. Thornton, A. S. Thrysoe, P. A. Tigwell, N. Tipton, I. Tiseanu, H. Tojo, M. Tokitani, P. Tolias, M. Tomes, P. Tonner, M. Towndrow, P. Trimble, M. Tripsky, M. Tsalas, P. Tsavalas, D. Tskhakaya jun, I. Turner, M. M. Turner, M. Turnyanskiy, G. Tvalashvili, S. G. J. Tyrrell, A. Uccello, Z. Ul-Abidin, J. Uljanovs, D. Ulyatt, H. Urano, I. Uytdenhouwen, A. P. Vadgama, D. Valcarcel, M. Valentinuzzi, M. Valisa, P. Vallejos Olivares, M. Valovic, M. Van De Mortel, D. Van Eester, W. Van Renterghem, G. J. van Rooij, J. Varje, S. Varoutis, S. Vartanian, K. Vasava, T. Vasilopoulou, J. Vega, G. Verdoolaege, R. Verhoeven, C. Verona, G. Verona Rinati, E. Veshchev, N. Vianello, J. Vicente, E. Viezzer, S. Villari, F. Villone, P. Vincenzi, I. Vinyar, B. Viola, A. Vitins, Z. Vizvary, M. Vlad, I. Voitsekhovitch, P. Vondràcek, N. Vora, T. Vu, W. W. Pires de Sa, B. Wakeling, C. W. F. Waldon, N. Walkden, M. Walker, R. Walker, M. Walsh, E. Wang, N. Wang, S. Warder, R. J. Warren, J. Waterhouse, N. W. Watkins, C. Watts, T. Wauters, A. Weckmann, J. Weiland, H. Weisen, M. Weiszflog, C. Wellstood, A. T. West, M. R. Wheatley, S. Whetham, A. M. Whitehead, B. D. Whitehead, A. M. Widdowson, S. Wiesen, J. Wilkinson, J. Williams, M. Williams, A. R. Wilson, D. J. Wilson, H. R. Wilson, J. Wilson, M. Wischmeier, G. Withenshaw, A. Withycombe, D. M. Witts, D. Wood, R. Wood, C. Woodley, S. Wray, J. Wright, J. C. Wright, J. Wu, S. Wukitch, A. Wynn, T. Xu, D. Yadikin, W. Yanling, L. Yao, V. Yavorskij, M. G. Yoo, C. Young, D. Young, I. D. Young, R. Young, J. Zacks, R. Zagorski, F. S. Zaitsev, R. Zanino, A. Zarins, K. D. Zastrow, M. Zerbini, W. Zhang, Y. Zhou, E. Zilli, V. Zoita, S. Zoletnik, and I. Zychor
Subjects: Physics, QC1-999
Abstract: A global heat flux model based on a fractional derivative of plasma pressure is proposed for the heat transport in fusion plasmas. The degree of the fractional derivative of the heat flux, α, is defined through the power balance analysis of the steady state. The model was used to obtain the experimental values of α for a large database of the Joint European Torus (JET) carbon-wall as well as ITER like-wall plasmas. The fractional degrees of the electron heat flux are found to be α
Published: 2020
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27. Модернистський дискурс про скінченність людського життя в сплетінні філософських, релігійних і наукових підходів

Author: Glib M. Maslov
Subjects: філософська антропологія, смерть, песимізм, оптимізм, європейський модернізм, антропологічний проект, Political science, Philosophy (General), B1-5802
Abstract: Аналізуються дискусії в європейській (переважно - російській та італійській) періодиці кінця ХІХ - початку ХХ століття навколо проблеми скінченності людини і їх вплив на формування модерністської парадигми. Виявляючи аргументи на користь оптимістичної або песимістичної позиції у ставленні до проблеми смерті в науковій, релігійній та філософській спадщині епохи, робиться висновок, що культура не змогла запропонувати єдиного задовільного рішення для пом’якшення конфлікту між модерністської спрямованістю до вдосконалення людини і її смертністю.
Published: 2019
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28. The Review of the Monograph by V.A. Kutyrev. Man is the Age of Technologies, the Philosophy of Falsehood

Author: Vadim M. Maslov
Abstract: In his last major work, V.A. Kutyrev continued to reflect the growing process of humanitys self-denial in favor of the emerging post-outside-human reality. The seriousness of the situation the approach of the irrevocable point of singularity requires the formation of an effective philosophy of resistance. Anthropoconservatism should defend the human at the practical, political level.
Published: 2023

29. Molecular Dynamics and Experimental Study of the Effect of CeF3 and NdF3 Additives on the Physical Properties of FLiNaK

Author: A. Y. Galashev, O. R. Rakhmanova, K. A. Abramova, K. P. Katin, M. M. Maslov, O. Y. Tkacheva, A. V. Rudenko, A. A. Kataev, and Y. P. Zaikov
Subjects: Materials Chemistry, Physical and Theoretical Chemistry, Surfaces, Coatings and Films
Published: 2023

30. Anisotropic Carrier Mobility and Spectral Fingerprints of Two-Dimensional γ-Phosphorus Carbide with Antisite Defects

Author: Konstantin P. Katin, Mikhail M. Maslov, Vladimir R. Nikitenko, Alexey I. Kochaev, Savas Kaya, and Oleg V. Prezhdo
Subjects: General Materials Science, Physical and Theoretical Chemistry
Abstract: We apply density functional theory to study carrier mobility in a γ-phosphorus carbide monolayer. Although previous calculations predicted high and anisotropic mobility in this material, we show that the mobility can be significantly influenced by common antisite defects. We demonstrate that at equilibrium concentrations defects do not inhibit carrier mobility up to temperatures of 1000 K. However, defects can change the mobility at high nonequilibrium concentrations of about 10
Published: 2022

31. Removal of erythrosine B dye from wastewater using chitosan boric acid composite material: Experimental and density functional theory findings

Author: Hüseyin Fatih Çetinkaya, Meltem Sarıoğlu Cebeci, Savaş Kaya, Nida Shams Jalbani, Mikhail M. Maslov, Riadh Marzouki, and Mühendislik Fakültesi
Subjects: adsorption, boric acid, chitosan, composite, DFT, erythrosine B, Organic Chemistry, Physical and Theoretical Chemistry
Abstract: In this study, the chitosan boric acid (Ch-B) composite has been prepared and characterized with sophisticated analytical techniques such as FT-IR, SEM, and EDX. The prepared Ch-B adsorbent was applied for the adsorption of erythrosine B (EB) dye from water samples under the optimized parameters of pH, adsorbent dosage, time, and temperature. Results shows that the Ch-B adsorbent removes 96.5% of EB dye at pH 5, using 0.05 g of adsorbent. The adsorption equilibrium data have been subject to the Langmuir, Freundlich, and D-R adsorption equilibrium models, which demonstrates that the Freundlich model was the best fit with good correlation coefficient value (R2 = 0.991), while energy E (9.18 KJ mol 1) calculated from D-R model suggested that the physical adsorption nature of the adsorption. Beside this, the thermodynamic and kinetic experiments were performed to check the feasibility and adsorption mechanism of EB-dye onto Ch-B adsorbent, which shows that the adsorption is endothermic (ΔH = 0.124) and spontaneous in nature due to the negative values of Gibbs free energy (i.e., ΔG KJ mol 1 = 13.01, 17.06, and 17.60). The kinetic models show that the adsorption equilibrium is best fitted with pseudo second order kinetic model due to good correlation coefficient (R2 = 0.99). Moreover, the interaction phenomenon between adsorbent and adsorbate was analyzed through DFT calculations.
Published: 2023

32. The role of isotope mass and transport for H-mode access in tritium containing plasmas at JET with ITER-like wall

Author: G Birkenmeier, E R Solano, I S Carvalho, J C Hillesheim, E Delabie, E Lerche, D Taylor, D Gallart, M J Mantsinen, C Silva, C Angioni, F Ryter, P Carvalho, M Fontana, E Pawelec, S A Silburn, P Sirén, S Aleiferis, J Bernardo, A Boboc, D Douai, P Puglia, P Jacquet, E Litherland-Smith, I Jepu, D Kos, H J Sun, A Shaw, D King, B Viola, R Henriques, K K Kirov, M Baruzzo, J Garcia, A Hakola, A Huber, E Joffrin, D Keeling, A Kappatou, M Lennholm, P Lomas, E de la Luna, C F Maggi, J Mailloux, M Maslov, F G Rimini, N Vianello, G Verdoolaege, H Weisen, M Wischmeier, Barcelona Supercomputing Center, and JET Contributors
Subjects: Isòtops, Física [Àrees temàtiques de la UPC], D-T plasma operation, regime, Condensed Matter Physics, L-H transition, isotope effects, Nuclear Energy and Engineering, Simulació per ordinador, tritium plasmas, transport, Nuclear fusion, isotope mixtures, Tranasport, Tokamaks, Física::Física de fluids::Física de plasmes [Àrees temàtiques de la UPC], l-h transition, d-t plasma operation
Abstract: The required heating power, P L H , to access the high confinement regime (H-mode) in tritium containing plasmas is investigated in JET with ITER-like wall at a toroidal magnetic field of B t = 1.8 T and a plasma current of I p = 1.7 MA. P L H , also referred to as the L-H power threshold, is determined in plasmas of pure tritium as well as mixtures of hydrogen with tritium (H-T) and mixtures of deuterium with tritium (D-T), and is compared to the L-H power threshold in plasmas of pure hydrogen and pure deuterium. It is found that, for otherwise constant parameters, P L H is not the same in plasmas with the same effective isotope mass, A e f f , when they differ in their isotope composition. Thus, A e f f is not sufficient to describe the isotope effect of P L H in a consistent manner for all considered isotopes and isotope mixtures. The electron temperature profiles measured at the L-H transition in the outer half of the radius are very similar for all isotopes and isotope mixtures, despite the fact that the L-H power threshold varies by a factor of about six. This finding, together with the observation of an offset linear relation between the L-H power threshold, P L H , and an effective heat diffusivity, χ e f f , indicates that the composition-dependent heat transport in the low confinement mode (L-mode) determines, how much power is needed to reach the necessary electron temperatures at the edge, and hence P L H .
Published: 2023

33. Routing of Floods of Rare Occurrence in the Valley of the Sulak River at the Facilities of the Dagestan Branch

Author: T. G. Gamzatov, A. A. Zhevlakov, V. N. Kiselev, D. M. Maslov, and N. V. Reutskiy
Subjects: Energy Engineering and Power Technology
Published: 2022

34. Fluorinated carbon and boron nitride fullerenes for drug Delivery: Computational study of structure and adsorption

Author: Elizaveta B. Kalika, Konstantin P. Katin, Alexey I. Kochaev, Savas Kaya, Mustafa Elik, Mikhail M. Maslov, and Eğitim Fakültesi
Subjects: Fluorination Fluorinated fullerenes B12N12 C60 Drug delivery Density functional theory, Materials Chemistry, Physical and Theoretical Chemistry, Condensed Matter Physics, Spectroscopy, Atomic and Molecular Physics, and Optics, Electronic, Optical and Magnetic Materials
Abstract: We applied a genetic algorithm combined with the B3LYP/6-311G** approach to determine the structures of low-energy isomers of partially fluorinated fullerenes, the number of which is combinatorically huge. We found that the effective interaction of fluorine atoms on the fullerene surface can not be described within the pair approximation with sufficient accuracy. For the smallest C20 fullerene, the most robust bonding with fluorine was observed in the C20F2 isomer, whereas further fluorination was less feasible. For C60 fullerene, the most thermodynamically stable isomers were C60F2 and C60Fm with m about 40. Effective attraction energy of adsorbed fluorine atom with OH, NH2, and COOH functional groups on the C60 fullerene surface is about 1.24 eV. Vibration analysis of the stable C60Fm isomers clarified the fre- quencies shifts during the gradual fluorination. As to fluorinated derivatives of boron nitride cages, some of them possess extreme distortions under low fluorination. However, half- and fully-fluorinated BN fullerenes demonstrate moderate strain and strong van-der-Waals interaction with doxorubicin drug. Loading of doxorubicin on both carbon and boron nitride fullerenes with varying degrees of fluorination confirmed that fluorine concentration defines the energy of the fullerene-drug interaction. A half- fluorinated B12N12F12 cage provides the most substantial adsorption, as the fluorine atoms on its surface are more moveable and can ‘‘adjust” to the DOX molecule. Ó 2022 Elsevier B.V. All rights reserved.
Published: 2023

35. Biosorption of lead ions (Pb2+) from water samples using dried Lemna minor biomass: experimental and density functional theory studies

Author: Savaş Kaya, Serap Çetinkaya, Nida Shams Jalbani, Ali Fazıl Yenidünya, Nurşah Kütük, Ergün Kasaka, and Mikhail M. Maslov
Subjects: Renewable Energy, Sustainability and the Environment
Published: 2023

36. Ecological assessment of pesticides

Author: R. Aptikaev, A. Astaykina, V. Gorbatov, E. Karavanova, A. Kokoreva, V. Kolupaeva, S. Lugansky, M. Maslov, R. Streletskii, and V. Tikhonov
Abstract: Methodological recommendations summarize and systematize the results of scientific and expert activities of the Faculty of Soil Science of Moscow State University on the ecological assessment of pesticides registering in the Russian Federation. This guideline describes the registration requirements for pesticides, laboratory and field methods of their testing, tools for predicting concentrations of pesticides in soil, ground and surface waters, and atmospheric air. Procedures for assessing the hazard and risk of pesticides for the environment and non-target species of wildlife organisms are proposed.
Published: 2023

37. Incorporation of graphene oxide to metal‐free phthalocyanine through hydrogen bonding for optoelectronic applications: An experimental and computational study

Author: Ebru Yabaş, Ebru Şenadım‐Tüzemen, Savaş Kaya, Michael M. Maslov, and Fuat Erden
Subjects: Organic Chemistry, Physical and Theoretical Chemistry
Published: 2023

38. Ab initio Study of Hydrogen Adsorption on Metal-Decorated Borophene-Graphene Bilayer

Author: Konstantin S. Grishakov, Konstantin P. Katin, Alexey I. Kochaev, Savas Kaya, Margarita A. Gimaldinova, and Mikhail M. Maslov
Subjects: hydrogen evolution reaction, borophene, graphene, single-atom catalyst, density functional theory, Technology
Abstract: We studied the hydrogen adsorption on the surface of a covalently bonded bilayer borophene-graphene heterostructure decorated with Pt, Ni, Ag, and Cu atoms. Due to its structure, the borophene-graphene bilayer combines borophene activity with the mechanical stability of graphene. Based on the density functional theory calculations, we determined the energies and preferred adsorption sites of these metal atoms on the heterostructure’s borophene surface. Since boron atoms in different positions can have different reactivities with respect to metal atoms, we considered seven possible adsorption positions. According to our calculations, all three metals adsorb in the top position above the boron atom and demonstrate catalytic activity. Among the metals considered, copper had the best characteristics. Copper-decorated heterostructure possesses a feasible near-zero overpotential for hydrogen evolution reaction. However, the borophene-graphene bilayer decorated with copper is unstable with respect to compression. Small deformations lead to irreversible structural changes in the system. Thus, compression cannot be used as an effective mechanism for additional potential reduction.
Published: 2021
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39. A Combined Study on Degradation Mechanism of Reactive Orange 16 through Fenton‐like Process: Experimental Studies and Density Functional Theoretical Findings

Author: Sayiter Yildiz, Gamze Topal Canbaz, Savaş Kaya, and Mikhail M. Maslov
Subjects: General Chemistry
Published: 2022

40. Stone–Wales Bilayer Graphene: Structure, Stability, and Interlayer Heat Transfer

Author: A. I. Podlivaev, Mikhail M. Maslov, Konstantin P. Katin, and Konstantin S. Grishakov
Subjects: Molecular dynamics, Materials science, Tight binding, Physics and Astronomy (miscellaneous), Solid-state physics, Chemical physics, Graphene, law, Bilayer, Heat transfer, Bilayer graphene, Intensity (heat transfer), law.invention
Abstract: The structure, stability, and interlayer heat transfer of Stone–Wales bilayer graphene have been studied within a nonorthogonal tight binding model. The most stable configuration has been identified among several metastable isomers differing in the mutual arrangement of the layers. It has been established that the structure under consideration is characterized by a stronger interlayer interaction than bilayer graphene, but its stiffness in the vertical direction is 17% smaller. The heat transfer between two layers of Stone–Wales graphene, one of which is initially cooled to 0 K and the second is heated to 77−7000 K, has been studied by the molecular dynamics method. The strain dependence of the interlayer heat transfer of the bilayer structure under study has been determined. It has been shown that the intensity of interlayer heat transfer strongly depends on the temperature and strain. Features of the interlayer interaction in Stone–Wales bilayer graphene that are atypical of usual bilayer graphene have been revealed and explained.
Published: 2021

41. Investigating the optical, electronic, magnetic properties and DFT of NiO films prepared using RF sputtering with various argon pressures

Author: Hicret Hopoğlu, Dogan Kaya, Mikhail M. Maslov, Savas Kaya, İlkay Demir, İsmail Altuntaş, Fatih Ungan, Mustafa Akyol, Ahmet Ekicibil, and Ebru Şenadım Tüzemen
Subjects: Electrical and Electronic Engineering, Condensed Matter Physics, Electronic, Optical and Magnetic Materials
Published: 2023

42. Hypercubane covalent crystals: Insight from density functional theory

Author: Mikhail M. Maslov, Alexey I. Kochaev, Margarita A. Gimaldinova, Anastasiya A. Grekova, and Konstantin P. Katin
Subjects: Mechanics of Materials, Materials Chemistry, General Materials Science
Published: 2023

43. On ionic transport through pores in a borophene–graphene membrane

Author: A. Kochaev, K. Katin, and M. Maslov
Subjects: Biomaterials, Colloid and Surface Chemistry, Polymers and Plastics, Materials Chemistry, Catalysis, Electronic, Optical and Magnetic Materials
Published: 2023

44. Combination of doped amorphous carbon based dispersive solid phase extraction with ionic liquid-based DLLME for the extraction of aromatic amines from leather industries wastewater; Theoretical and experimental insights

Author: Mahboob Nemati, Mir Ali Farajzadeh, Nail Altunay, Mustafa Tuzen, Savaş Kaya, Mikhail M. Maslov, and Mohammad Reza Afshar Mogaddam
Subjects: Inorganic Chemistry, Organic Chemistry, Spectroscopy, Analytical Chemistry
Published: 2023

45. Analytical and MonteCarlo approaches to infer the total gamma ray emission from the JET tokamak

Author: G. Marcer, A. Zohar, A. Dal Molin, D. Rigamonti, M. Rebai, M. Nocente, E. Panontin, G. Croci, G. Gorini, G. Grosso, A. Muraro, E. Perelli Cippo, O. Putignano, E. de la Luna, Z. Ghani, S. Conroy, J. Garcia, Y. Kazakov, V. Kiptily, M. Maslov, M.F.F. Nave, J. Ongena, and M. Tardocchi
Subjects: Instrumentation, Mathematical Physics
Abstract: A single gamma-ray spectrometer installed at the end of a collimator can be used to infer the total emission from a tokamak plasma if the transport of gamma-rays from the plasma to the detector is known. In such analysis, the plasma emission profile plays a fundamental role, since it impacts the fraction of plasma volume intercepted by the detector line of sight. In this work, the DT 17 MeV fusion gamma-rays emission profile of the JET discharge #99608 from second 46 to 48 has been estimated both with the TRANSP code and reconstructed through tomographic inversion based on the neutron camera data, assuming that fusion gamma-rays have the same profile as the 14 MeV fusion neutrons. The gamma-ray transport has been evaluated both by MonteCarlo simulations and analytical calculations. By combining MonteCarlo and analytical evaluations of the gamma-ray transport in different ways with the estimated radiation emission profile, we provide four different routes to determine the total gamma-ray yield from measurements whose results agree within better than 10%.
Published: 2023

46. Adsorption of 40 low molecular weight drugs on pristine and fluorinated C60 fullerenes: Ab initio, statistical and neural networks analysis

Author: Elizaveta B. Kalika, Nikolay V. Bondarev, Konstantin P. Katin, Alexey I. Kochaev, Anastasiya A. Grekova, Savas Kaya, Yusupbek A. Bauetdinov, and Mikhail M. Maslov
Subjects: Materials Chemistry, Physical and Theoretical Chemistry, Condensed Matter Physics, Spectroscopy, Atomic and Molecular Physics, and Optics, Electronic, Optical and Magnetic Materials
Published: 2023

47. Improved lithium-ion batteries and their communication with hydrogen power

Author: Konstantin P. Katin, Ksenia A. Ivanichkina, Alexander Y. Galashev, Mikhail M. Maslov, O. R. Rakhmanova, and Alexey S. Vorob’ev
Subjects: Battery (electricity), Materials science, Renewable Energy, Sustainability and the Environment, Silicene, business.industry, Energy Engineering and Power Technology, chemistry.chemical_element, 02 engineering and technology, 010402 general chemistry, 021001 nanoscience & nanotechnology, Condensed Matter Physics, 01 natural sciences, Energy storage, 0104 chemical sciences, Power (physics), Anode, Fuel Technology, chemistry, Hydrogen fuel, Electrode, Lithium, 0210 nano-technology, Process engineering, business
Abstract: Self-contained power supplies and energy storage continue to improve. The criteria that determine their development include efficiency, safety, adaptability, modifiability, and a number of others. In this work, one of the ways to improve the lithium-ion battery by using a new negative electrode is considered. The possibilities of applicability of the improved lithium-ion battery are discussed, its advantages and disadvantages in relation to a hydrogen fuel cell and power sources using hydrogen fuel are considered. The study of the functioning of the new anode, the material of which is a two-layer silicene on a nickel substrate, is carried out at the atomic level. Improvement of the anode characteristics can be achieved by subjecting it to the neutron doping. Li-ion batteries with an improved anode will have higher charging capacity and power, faster charging and improved safety.
Published: 2021

48. Theoretical Study of High-Frequency Response of InGaAs/AlAs Double-Barrier Nanostructures

Author: Konstantin S. Grishakov, Vladimir F. Elesin, Mikhail M. Maslov, and Konstantin P. Katin
Subjects: Materials of engineering and construction. Mechanics of materials, TA401-492
Abstract: The presented article contains the numerical calculations of the InGaAs/AlAs resonant tunneling diode’s (RTD) response to the AC electric field of a wide range of amplitudes and frequencies. These calculations have been performed within the coherent quantum-mechanical model that is based on the solution of the time-dependent Schrödinger equation with exact open boundary conditions. It is shown that as the field amplitude increases, at high frequencies, where ħω>Γ (Γ is the width of the resonant energy level), the active current can reach high values comparable to the direct current value in resonance. This indicates the implementation of the quantum regime for RTD when radiative transitions are between quasi-energetic levels and the resonant energy level. Moreover, there is an excitement of higher quasi-energetic levels in AC electric fields, which in particular results in a slow droop of the active current as the field amplitude increases. It also results in potentially abrupt changes of the operating point position by the ħω value. This makes it possible to achieve relatively high output powers of InGaAs/AlAs RTD having an order of 105 W/cm2 at high frequencies.
Published: 2017
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49. Role of NBI fuelling in contributing to density peaking between the ICRH and NBI identity plasmas on JET

Author: T. Tala, F. Eriksson, P. Mantica, A. Mariani, A. Salmi, E.R. Solano, I.S. Carvalho, A. Chomiczewska, E. Delabie, J. Ferreira, E. Fransson, L. Horvath, P. Jacquet, D. King, A. Kirjasuo, S. Leerink, E. Lerche, C. Maggi, M. Marin, M. Maslov, S. Menmuir, R.B. Morales, V. Naulin, M.F.F. Nave, H. Nordman, C. Perez von Thun, P.A. Schneider, M. Sertoli, K. Tanaka, JET Contributors, VTT Technical Research Centre of Finland, JET, CNR-ENEA-EURATOM Association, University of Milan - Bicocca, CIEMAT, University of Lisbon, IPPLM, Chalmers University of Technology, Department of Applied Physics, Royal Military Academy, Dutch Institute for Fundamental Energy Research, Technical University of Denmark, Max-Planck-Institut für Plasmaphysik, Tokamak Energy Ltd, National Institute for Fusion Science, Aalto-yliopisto, Aalto University, Tala, T, Eriksson, F, Mantica, P, Mariani, A, Salmi, A, Solano, E, Carvalho, I, Chomiczewska, A, Delabie, E, Ferreira, J, Fransson, E, Horvath, L, Jacquet, P, King, D, Kirjasuo, A, Leerink, S, Lerche, E, Maggi, C, Marin, M, Maslov, M, Menmuir, S, Morales, R, Naulin, V, Nave, M, Nordman, H, Perez Von Thun, C, Schneider, P, Sertoli, M, Tanaka, K, Contributors, J, and JET Contributors
Subjects: Nuclear and High Energy Physics, Other Physics Topics, dimensioness identity plasma, particle transport, NBI fuelling, particle transport modelling, Energy Engineering, Condensed Matter Physics, Fusion, Plasma and Space Physics, density peaking
Abstract: Density peaking has been studied between an ICRH and NBI identity plasma in JET. The comparison shows that 8 MW of NBI heating/fueling increases the density peaking by a factor of two, being R/L n = 0.45 for the ICRH pulse and R/L n = 0.93 for the NBI one averaged radially over ρ tor = 0.4, 0.8. The dimensionless profiles of q, ρ *, υ *, β n and T i/T e ≈ 1 were matched within 5% difference except in the central part of the plasma (ρ tor < 0.3). The difference in the curvature pinch (same q-profile) and thermo-pinch (T i = T e) between the ICRH and NBI discharges is virtually zero. Both the gyro-kinetic simulations and integrated modelling strongly support the experimental result where the NBI fuelling is the main contributor to the density peaking for this identity pair. It is to be noted here that the integrated modeling does not reproduce the measured electron density profiles, but approximately reproduces the difference in the density profiles between the ICRH and NBI discharge. Based on these modelling results and the analyses, the differences between the two pulses in impurities, fast ions (FIs), toroidal rotation and radiation do not cause any such changes in the background transport that would invalidate the experimental result where the NBI fuelling is the main contributor to the density peaking. This result of R/L n increasing by a factor of 2 per 8 MW of NBI power is valid for the ion temperature gradient dominated low power H-mode plasmas. However, some of the physics processes influencing particle transport, like rotation, turbulence and FI content scale with power, and therefore, the simple scaling on the role of the NBI fuelling in JET is not necessarily the same under higher power conditions or in larger devices.
Published: 2022

50. Interlayer Heat Conductivity and Thermal Stability of Distorted Bilayer Graphene

Author: Konstantin S. Grishakov, A. I. Podlivaev, Konstantin P. Katin, and Mikhail M. Maslov
Subjects: Materials science, Physics and Astronomy (miscellaneous), Solid-state physics, Condensed matter physics, Graphene, 01 natural sciences, 010305 fluids & plasmas, law.invention, Thermal conductivity, law, 0103 physical sciences, Heat transfer, Thermal stability, 010306 general physics, Bilayer graphene, Intensity (heat transfer), Order of magnitude
Abstract: The nonorthogonal tight-binding potential is augmented by long-range terms needed for a correct description of the interlayer interaction in bilayer graphene. The molecular dynamics method is used to study the heat transfer between two distorted graphene layers, one of which is initially cooled down to 0 K, and the second one is heated up to 77−7000 K. The characteristic time of the heat transfer depending on the initial temperature of the heated layer and the distortion of the layers is determined. It is demonstrated that both factors significantly affect the intensity of interlayer heat transfer. It is found that, during the characteristic time of temperature equalization, thermally induced defects of various types, including melting, separation of the layers, and tangential shear of the heated layer, can appear in the system. It is shown that the formation of thermally induced defects can result in more than an order of magnitude increase in the rate of interlayer heat transfer.
Published: 2021

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