Nuclear Fusion最新文献

{"title":"Diagnosing inertial confinement fusion ignition","authors":"A.S. Moore, L. Divol, B. Bachmann, R. Bionta, D. Bradley, D.T. Casey, P. Celliers, H. Chen, A. Do, E. Dewald, M. Eckart, D. Fittinghoff, J. Frenje, M. Gatu-Johnson, H. Geppert-Kleinrath, V. Geppert-Kleinrath, G. Grim, K. Hahn, M. Hohenberger, J. Holder, O. Hurricane, N. Izumi, S. Kerr, S.F. Khan, J.D. Kilkenny, Y. Kim, B. Kozioziemski, N. Lemos, A.G. MacPhee, P. Michel, M. Millot, K.D. Meaney, S. Nagel, A. Pak, J.E. Ralph, J.S. Ross, M.S. Rubery, D.J. Schlossberg, V. Smalyuk, G. Swadling, R. Tommasini, C. Trosseille, A.B. Zylstra, A. Mackinnon, J.D. Moody, O.L. Landen, R. Town","doi":"10.1088/1741-4326/ad703b","DOIUrl":"https://doi.org/10.1088/1741-4326/ad703b","url":null,"abstract":"Fusion ignition by inertial confinement requires compression and heating of the fusion fuel to temperatures in excess of 5 keV and densities exceeding hundreds of g/cc. In August 2021, this scientific milestone was surpassed at the National Ignition Facility (NIF), when the Lawson criterion for ignition was exceeded generating 1.37MJ of fusion energy (Abu-Shawareb <italic toggle=\"yes\">et al</italic> 2022 <italic toggle=\"yes\">Phys. Rev. Lett.</italic> <bold>129</bold> 075001), and then in December 2022 target gain &gt;1 was realized with the production of 3.1MJ of fusion energy from a target driven by 2.0MJ of laser energy (Abu-Shawareb <italic toggle=\"yes\">et al</italic> 2024 <italic toggle=\"yes\">Phys. Rev. Lett.</italic> <bold>132</bold> 065102). At the NIF, inertial confinement fusion research primarily uses a laser indirect drive in which the fusion capsule is surrounded by a high-Z enclosure (‘hohlraum’) used to convert the directed laser energy into a symmetric x-ray drive on the capsule. Precise measurements of the plasma conditions, x-rays, <italic toggle=\"yes\">γ</italic>-rays and neutrons produced are key to understanding the pathway to higher performance. This paper discusses the diagnostics and measurement techniques developed to understand these experiments, focusing on three main topics: (1) key diagnostic developments for achieving igniting plasmas, (2) novel signatures related to thermonuclear burn and (3) advances to diagnostic capabilities in the igniting regime with a perspective toward developments for intertial fusion energy.","PeriodicalId":19379,"journal":{"name":"Nuclear Fusion","volume":"20 1","pages":""},"PeriodicalIF":3.3,"publicationDate":"2024-09-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142212114","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Quantification of locked mode instability triggered by a change in confinement","authors":"M. Peterka, J. Seidl, T. Markovic, A. Loarte, N.C. Logan, J.-K. Park, P. Cahyna, J. Havlicek, M. Imrisek, L. Kripner, R. Panek, M. Sos, P. Bilkova, K. Bogar, P. Bohm, A. Casolari, Y. Gribov, O. Grover, P. Hacek, M. Hron, K. Kovarik, M. Tomes, D. Tskhakaya, J. Varju, P. Vondracek, V. Weinzettl, the COMPASS Teama","doi":"10.1088/1741-4326/ad6ce7","DOIUrl":"https://doi.org/10.1088/1741-4326/ad6ce7","url":null,"abstract":"This work presents the first analysis of the disruptive locked mode (LM) triggered by the dynamics of a confinement change. It shows that, under certain conditions, the LM threshold during the transient is significantly lower than expected from steady states. We investigate the sensitivity to a controlled <italic toggle=\"yes\">n</italic> = 1 error field (EF) activated prior to the L-H transition in the COMPASS tokamak, at <italic toggle=\"yes\">q</italic>₉₅ ∼ 3, <italic toggle=\"yes\">β</italic>_N ∼ 1, and using EF coils on the high-field side of the vessel. A threshold for EF penetration subsequent to the L-H transition is identified, which shows no significant trend with density or applied torque, and is an apparent consequence of the reduced intrinsic rotation of the 2/1 mode during this transient phase. This finding challenges the assumption made in theoretical and empirical works that natural mode rotation can be predicted by global plasma parameters and urges against using any parametric EF penetration scaling derived from steady-state experiments to define the EF correction strategy in the entire discharge. Furthermore, even at EFs below the identified penetration threshold, disruptive locking of sawtooth-seeded 2/1 tearing modes is observed after about 30% of L-H transitions without external torque.","PeriodicalId":19379,"journal":{"name":"Nuclear Fusion","volume":"76 2 1","pages":""},"PeriodicalIF":3.3,"publicationDate":"2024-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142212116","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Quasilinear theory and modelling of gyrokinetic turbulent transport in tokamaks","authors":"G. Staebler, C. Bourdelle, J. Citrin, R. Waltz","doi":"10.1088/1741-4326/ad6ba5","DOIUrl":"https://doi.org/10.1088/1741-4326/ad6ba5","url":null,"abstract":"The theory, development, and validation of reduced quasilinear models of gyrokinetic turbulent transport in the closed flux surface core of tokamaks is reviewed. In combination with neoclassical collisional transport, these models are successful in accurately predicting core tokamak plasma temperature, density, rotation, and impurity profiles in a variety of confinement regimes. Refined experimental tests have been performed to validate the predictions of the quasilinear models, probing changes in the dominant gyrokinetic instabilities, as reflected in fluctuation measurements, cross-phases, and transport properties. These tests continue to produce a deeper understanding of the complex mix of instabilities at both electron and ion gyroradius scales.","PeriodicalId":19379,"journal":{"name":"Nuclear Fusion","volume":"24 1","pages":""},"PeriodicalIF":3.3,"publicationDate":"2024-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142212115","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Resistive wall tearing mode disruptions","authors":"H.R. Strauss, B.E. Chapman, B.C. Lyons","doi":"10.1088/1741-4326/ad7272","DOIUrl":"https://doi.org/10.1088/1741-4326/ad7272","url":null,"abstract":"This paper deals with resistive wall tearing mode (RWTM) disruptions. RWTMs are closely related to resistive wall modes. RWTMs are tearing modes whose linear and nonlinear behavior is strongly dependent on the resistive wall outside the plasma. The consequence for ITER, is that the thermal quench timescale could be much longer than previously conjectured. Active feedback stabilization is another possible way to mitigate or prevent RWTM disruptions. Simulations of RWTM disruptions are reviewed for DIII-D and MST. MST has a longer resistive wall time than ITER, and disruptions are not observed experimentally when MST is operated as a standard tokamak. Simulations indicate that the RWTM disruption time scale is longer than the experimental shot time. Edge cooling causes contraction of the current profile, which can destabilize RWTMs. The equilibria studied here have the <italic toggle=\"yes\">q</italic> = 2 rational surface close to the edge of the plasma, and low current density between the <italic toggle=\"yes\">q</italic> = 2 surface and the wall. A sequence of low edge current model equilibria has major disruptions only for a resistive, not ideal, wall, and edge <inline-formula>\u0000<tex-math><?CDATA $q unicode{x2A7D} 3.4.$?></tex-math><mml:math overflow=\"scroll\"><mml:mrow><mml:mi>q</mml:mi><mml:mtext>⩽</mml:mtext><mml:mn>3.4</mml:mn><mml:mo>.</mml:mo></mml:mrow></mml:math><inline-graphic xlink:href=\"nfad7272ieqn1.gif\"></inline-graphic></inline-formula> This is consistent with regimes of tokamak disruptivity, suggesting that tokamak disruptions caused by edge cooling at low edge <italic toggle=\"yes\">q</italic> could be RWTMs.","PeriodicalId":19379,"journal":{"name":"Nuclear Fusion","volume":"7 1","pages":""},"PeriodicalIF":3.3,"publicationDate":"2024-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142212148","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Use of differential plasma rotation to prevent disruptive tearing mode onset from 3-wave coupling","authors":"N.J. Richner, L. Bardóczi, J.D. Callen, R.J. La Haye, N.C. Logan, E.J. Strait","doi":"10.1088/1741-4326/ad7273","DOIUrl":"https://doi.org/10.1088/1741-4326/ad7273","url":null,"abstract":"Plasma differential rotation is found to be capable of preventing disruptive neoclassical tearing modes (NTMs) seeded by nonlinear three-wave coupling. As tearing modes degrade confinement and can lead to disruptions, stabilization strategies are crucial to the successful operation of future devices. In ITER-relevant scenarios on DIII-D, rotationally coupled <inline-formula>\u0000<tex-math><?CDATA $m/n$?></tex-math><mml:math overflow=\"scroll\"><mml:mrow><mml:mi>m</mml:mi><mml:mrow><mml:mo>/</mml:mo></mml:mrow><mml:mi>n</mml:mi></mml:mrow></mml:math><inline-graphic xlink:href=\"nfad7273ieqn1.gif\"></inline-graphic></inline-formula> = 1/1 and 3/2 modes have been observed to drive 2/1 islands through three-wave coupling. The frequency of the driven 2/1 mode is set by matching conditions and the frequencies of the driving modes. When the driven mode frequency matches the local plasma rotation frequency, e.g. at low differential rotation, the driven 2/1 island can grow into a disruptive NTM. Using neutral beam torque as an actuator to scan the differential rotation, these experiments demonstrate that a sufficiently large frequency mismatch prevents destabilization of disruptive 2/1 NTMs by three-wave coupling. This work indicates that differential rotation can be used as an actuator to prevent NTMs seeded by three-wave coupling.","PeriodicalId":19379,"journal":{"name":"Nuclear Fusion","volume":"7 1","pages":""},"PeriodicalIF":3.3,"publicationDate":"2024-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142212120","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"FLARE: field line analysis and reconstruction for 3D boundary plasma modeling","authors":"H. Frerichs","doi":"10.1088/1741-4326/ad7303","DOIUrl":"https://doi.org/10.1088/1741-4326/ad7303","url":null,"abstract":"The FLARE code is a magnetic mesh generator that is integrated within a suite of tools for the analysis of the magnetic geometry in toroidal fusion devices. A magnetic mesh is constructed from field line segments and permits fast reconstruction of field lines in 3D boundary plasma codes such as EMC3-EIRENE. Both intrinsically non-axisymmetric configurations (stellarators) and those with symmetry breaking perturbations of an axisymmetric equilibrium (tokamaks) are supported. The code itself is written in Modern Fortran with MPI support for parallel computing, and it incorporates object-oriented programming for the definition of the magnetic field and the material surface geometry. Extended derived types for a number of different magnetohydrodynamic equilibrium and plasma response models are implemented. The core element of FLARE is a field line tracer with adaptive step-size control, and this is integrated into tools for the construction of Poincaré maps and invariant manifolds of X-points. A collection of high-level procedures that generate output files for visualization is build on top of that. The analysis modules are build with Python frontends that facilitate customization of tasks and/or scripting of parameter scans.","PeriodicalId":19379,"journal":{"name":"Nuclear Fusion","volume":"64 1","pages":""},"PeriodicalIF":3.3,"publicationDate":"2024-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142212122","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Numerical study of a general criterion for divertor detachment control","authors":"Hao Yang, Guido Ciraolo, Olivier Février, Nicolas Fedorczak, Nicolas Rivals, Andreas Bierwage, Hugo Bufferand, Gloria L Falchetto, Tomohide Nakano, Patrick Tamain, Jérôme Bucalossi, the WEST teama","doi":"10.1088/1741-4326/ad6e07","DOIUrl":"https://doi.org/10.1088/1741-4326/ad6e07","url":null,"abstract":"The parameter &lt;inline-formula&gt;\u0000&lt;tex-math&gt;&lt;?CDATA $R_mathrm{D} = P_mathrm{rad}/P_mathrm{cond}$?&gt;&lt;/tex-math&gt;&lt;mml:math overflow=\"scroll\"&gt;&lt;mml:mrow&gt;&lt;mml:msub&gt;&lt;mml:mi&gt;R&lt;/mml:mi&gt;&lt;mml:mrow&gt;&lt;mml:mi mathvariant=\"normal\"&gt;D&lt;/mml:mi&gt;&lt;/mml:mrow&gt;&lt;/mml:msub&gt;&lt;mml:mo&gt;=&lt;/mml:mo&gt;&lt;mml:msub&gt;&lt;mml:mi&gt;P&lt;/mml:mi&gt;&lt;mml:mrow&gt;&lt;mml:mi&gt;rad&lt;/mml:mi&gt;&lt;/mml:mrow&gt;&lt;/mml:msub&gt;&lt;mml:mrow&gt;&lt;mml:mo&gt;/&lt;/mml:mo&gt;&lt;/mml:mrow&gt;&lt;mml:msub&gt;&lt;mml:mi&gt;P&lt;/mml:mi&gt;&lt;mml:mrow&gt;&lt;mml:mi&gt;cond&lt;/mml:mi&gt;&lt;/mml:mrow&gt;&lt;/mml:msub&gt;&lt;/mml:mrow&gt;&lt;/mml:math&gt;&lt;inline-graphic xlink:href=\"nfad6e07ieqn1.gif\"&gt;&lt;/inline-graphic&gt;&lt;/inline-formula&gt;, which measures the ratio of radiated power to conductive heat flux at downstream &lt;italic toggle=\"yes\"&gt;Scrape-Off-Layer&lt;/italic&gt; (SOL), is proposed as a robust and practically useful figure of merit for divertor detachment control. The simulations performed using the SOLEDGE3X-EIRENE code predict that the instant where &lt;inline-formula&gt;\u0000&lt;tex-math&gt;&lt;?CDATA $R_mathrm{D}$?&gt;&lt;/tex-math&gt;&lt;mml:math overflow=\"scroll\"&gt;&lt;mml:mrow&gt;&lt;mml:msub&gt;&lt;mml:mi&gt;R&lt;/mml:mi&gt;&lt;mml:mrow&gt;&lt;mml:mi mathvariant=\"normal\"&gt;D&lt;/mml:mi&gt;&lt;/mml:mrow&gt;&lt;/mml:msub&gt;&lt;/mml:mrow&gt;&lt;/mml:math&gt;&lt;inline-graphic xlink:href=\"nfad6e07ieqn2.gif\"&gt;&lt;/inline-graphic&gt;&lt;/inline-formula&gt; passes through unity (that is, when &lt;inline-formula&gt;\u0000&lt;tex-math&gt;&lt;?CDATA $P_mathrm{rad} approx P_mathrm{cond}$?&gt;&lt;/tex-math&gt;&lt;mml:math overflow=\"scroll\"&gt;&lt;mml:mrow&gt;&lt;mml:msub&gt;&lt;mml:mi&gt;P&lt;/mml:mi&gt;&lt;mml:mrow&gt;&lt;mml:mi&gt;rad&lt;/mml:mi&gt;&lt;/mml:mrow&gt;&lt;/mml:msub&gt;&lt;mml:mo&gt;≈&lt;/mml:mo&gt;&lt;mml:msub&gt;&lt;mml:mi&gt;P&lt;/mml:mi&gt;&lt;mml:mrow&gt;&lt;mml:mi&gt;cond&lt;/mml:mi&gt;&lt;/mml:mrow&gt;&lt;/mml:msub&gt;&lt;/mml:mrow&gt;&lt;/mml:math&gt;&lt;inline-graphic xlink:href=\"nfad6e07ieqn3.gif\"&gt;&lt;/inline-graphic&gt;&lt;/inline-formula&gt;) coincides with the detachment of the radiation front from the divertor target. Furthermore, as a function of &lt;inline-formula&gt;\u0000&lt;tex-math&gt;&lt;?CDATA $R_mathrm{D}$?&gt;&lt;/tex-math&gt;&lt;mml:math overflow=\"scroll\"&gt;&lt;mml:mrow&gt;&lt;mml:msub&gt;&lt;mml:mi&gt;R&lt;/mml:mi&gt;&lt;mml:mrow&gt;&lt;mml:mi mathvariant=\"normal\"&gt;D&lt;/mml:mi&gt;&lt;/mml:mrow&gt;&lt;/mml:msub&gt;&lt;/mml:mrow&gt;&lt;/mml:math&gt;&lt;inline-graphic xlink:href=\"nfad6e07ieqn4.gif\"&gt;&lt;/inline-graphic&gt;&lt;/inline-formula&gt;, there is a decrease in target temperature and an increase in the distance at which the radiation front detaches from the target. These simulations cover scenarios in WEST and TCV with different levels of confinement, divertor closure, impurity concentration, and input power. The physical rationale underlying the above definition of &lt;inline-formula&gt;\u0000&lt;tex-math&gt;&lt;?CDATA $R_mathrm{D}$?&gt;&lt;/tex-math&gt;&lt;mml:math overflow=\"scroll\"&gt;&lt;mml:mrow&gt;&lt;mml:msub&gt;&lt;mml:mi&gt;R&lt;/mml:mi&gt;&lt;mml:mrow&gt;&lt;mml:mi mathvariant=\"normal\"&gt;D&lt;/mml:mi&gt;&lt;/mml:mrow&gt;&lt;/mml:msub&gt;&lt;/mml:mrow&gt;&lt;/mml:math&gt;&lt;inline-graphic xlink:href=\"nfad6e07ieqn5.gif\"&gt;&lt;/inline-graphic&gt;&lt;/inline-formula&gt; is that when the divertor radiated power is comparable to the conductive heat flux, there will be a lack of energy reaching the target. Consequently, the radiation front detaches some distance from the divertor target. &lt;inline-formula&gt;\u0000&lt;tex-math&gt;&lt;?CDATA $R_mathrm{D}$?&gt;&lt;/tex-math&gt;&lt;mml:math overflow=\"scroll\"&gt;&lt;mml:mrow&gt;&lt;mm","PeriodicalId":19379,"journal":{"name":"Nuclear Fusion","volume":"63 1","pages":""},"PeriodicalIF":3.3,"publicationDate":"2024-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142212118","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The formation of an radial edge electric field due to finite ion orbit width effects is the possible root cause of the H-mode edge","authors":"G.J. Kramer, A. Bortolon, A. Diallo, R. Maingi","doi":"10.1088/1741-4326/ad7275","DOIUrl":"https://doi.org/10.1088/1741-4326/ad7275","url":null,"abstract":"Full orbit-following simulations of thermal ions show that finite ion-orbit width effects create charge separation near the last closed flux surface (LCFS) which generates a localized radial electric field. Experimentally, edge electric fields are observed in H-mode plasmas and they are necessary for the edge turbulence suppression via the <inline-formula>\u0000<tex-math><?CDATA $boldsymbol{ E times B }$?></tex-math><mml:math overflow=\"scroll\"><mml:mrow><mml:mi mathvariant=\"bold-italic\">E</mml:mi><mml:mo mathvariant=\"bold\">×</mml:mo><mml:mi mathvariant=\"bold-italic\">B</mml:mi></mml:mrow></mml:math><inline-graphic xlink:href=\"nfad7275ieqn1.gif\"></inline-graphic></inline-formula> flow shear mechanism. Confined trapped (and to a lesser extent co-passing) ions near the plasma edge form a positive charge distribution outside the LCFS, while thermal electrons are tied more tightly to field lines owing to their small mass and are poorly confined outside the LCFS, hence charge neutrality is violated outside the LCFS. A large number of reported observations from spherical and conventional tokamaks support the results from the simulations although the simulations were not performed fully self consistently. The results suggest ways to lower the H-mode power threshold and optimize the H-mode plasma edge.","PeriodicalId":19379,"journal":{"name":"Nuclear Fusion","volume":"21 1","pages":""},"PeriodicalIF":3.3,"publicationDate":"2024-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142212121","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Physics basis for the divertor tokamak test facility","authors":"F. Crisanti, R. Ambrosino, M.V. Falessi, L. Gabellieri, G. Giruzzi, G. Granucci, P. Innocente, P. Mantica, G. Ramogida, G. Vlad, R. Albanese, E. Alessi, C. Angioni, P. Agostinetti, L. Aucone, F. Auriemma, B. Baiocchi, L. Balbinot, A. Balestri, T. Barberis, M. Baruzzo, T. Bolzonella, N. Bonanomi, D. Bonfiglio, S. Brezinsek, G. Calabrò, F. Cani, I. Casiraghi, A. Castaldo, C. Castaldo, M. Cavedon, S. Ceccuzzi, F. Cichocki, M. Ciotti, C. Day, C. De Piccoli, G. Dose, E. Emanueli, L. Frassinetti, L. Figini, V. Fusco, E. Giovannozzi, M. Gobbin, F. Koechi, A. Kryzhanovskyy, Y. Li, R. Lombroni, T. Luda, A. Mariani, P. Martin, C. Meineri, A. Murari, P. Muscente, F. Napoli, E. Nardon, R. Neu, M. Nocente, M. Notazio, S. Nowak, L. Pigatto, C. Piron, F. Porcelli, S. Roccella, G. Rubino, M. Scarpari, C. Sozzi, G. Spizzo, F. Subba, F. Taccogna, C. Tantos, D. Terranova, E. Tsitrone, A. Uccello, D. Van Eester, N. Vianello, P. Vincenzi, M. Wischmeier, F. Zonca","doi":"10.1088/1741-4326/ad6e06","DOIUrl":"https://doi.org/10.1088/1741-4326/ad6e06","url":null,"abstract":"This paper is dealing with the physics basis used for the design of the Divertor Tokamak Test facility (DTT), under construction in Frascati (DTT 2019 DTT interim design report (2019)) Italy, and with the description of the main target plasma scenarios of the device. The main goal of the facility will be the study of the power exhaust, intended as a fully integrated core-edge problem, and eventually to propose an optimized divertor for the European DEMO plant. The approach used to design the facility is described and their main features are reported, by using simulations performed by state-of-the-art codes both for the bulk and edge studies. A detailed analysis of MHD, including also the possibility to study disruption events and Energetic Particles physics is also reported. Eventually, a description of the ongoing work to build-up a Research Plan written and shared by the full EUROfusion community is presented.","PeriodicalId":19379,"journal":{"name":"Nuclear Fusion","volume":"91 1","pages":""},"PeriodicalIF":3.3,"publicationDate":"2024-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142212117","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Electron transport barrier and high confinement in configurations with internal islands close to the plasma edge of W7-X","authors":"N. Chaudhary, M. Hirsch, T. Andreeva, J. Geiger, R.C. Wolf, G.A. Wurden, the W7-X Teama","doi":"10.1088/1741-4326/ad703e","DOIUrl":"https://doi.org/10.1088/1741-4326/ad703e","url":null,"abstract":"The low magnetic shear in the Wendelstein 7-X (W7-X) stellarator makes it feasible to shape the separatrix by the large islands constituting an island-divertor, and this can be exploited to access various magnetic configurations, including samples of different internal island sizes and locations. To investigate the configuration effects on the plasma confinement, a configuration scan was performed by changing the coil currents to vary the rotational transform between values &lt;inline-formula&gt;\u0000&lt;tex-math&gt;&lt;?CDATA $5/4$?&gt;&lt;/tex-math&gt;&lt;mml:math overflow=\"scroll\"&gt;&lt;mml:mrow&gt;&lt;mml:mn&gt;5&lt;/mml:mn&gt;&lt;mml:mrow&gt;&lt;mml:mo&gt;/&lt;/mml:mo&gt;&lt;/mml:mrow&gt;&lt;mml:mn&gt;4&lt;/mml:mn&gt;&lt;/mml:mrow&gt;&lt;/mml:math&gt;&lt;inline-graphic xlink:href=\"nfad703eieqn1.gif\"&gt;&lt;/inline-graphic&gt;&lt;/inline-formula&gt; and &lt;inline-formula&gt;\u0000&lt;tex-math&gt;&lt;?CDATA $5/6$?&gt;&lt;/tex-math&gt;&lt;mml:math overflow=\"scroll\"&gt;&lt;mml:mrow&gt;&lt;mml:mn&gt;5&lt;/mml:mn&gt;&lt;mml:mrow&gt;&lt;mml:mo&gt;/&lt;/mml:mo&gt;&lt;/mml:mrow&gt;&lt;mml:mn&gt;6&lt;/mml:mn&gt;&lt;/mml:mrow&gt;&lt;/mml:math&gt;&lt;inline-graphic xlink:href=\"nfad703eieqn2.gif\"&gt;&lt;/inline-graphic&gt;&lt;/inline-formula&gt; at the plasma boundary with different power levels (2, 4, 6 MW) of electron cyclotron resonance heating (ECRH) at a maximum plasma density of &lt;inline-formula&gt;\u0000&lt;tex-math&gt;&lt;?CDATA $8 times 10^{19},textrm{m}^{-2}$?&gt;&lt;/tex-math&gt;&lt;mml:math overflow=\"scroll\"&gt;&lt;mml:mrow&gt;&lt;mml:mn&gt;8&lt;/mml:mn&gt;&lt;mml:mo&gt;×&lt;/mml:mo&gt;&lt;mml:msup&gt;&lt;mml:mn&gt;10&lt;/mml:mn&gt;&lt;mml:mrow&gt;&lt;mml:mn&gt;19&lt;/mml:mn&gt;&lt;/mml:mrow&gt;&lt;/mml:msup&gt;&lt;mml:mstyle scriptlevel=\"0\"&gt;&lt;/mml:mstyle&gt;&lt;mml:msup&gt;&lt;mml:mtext&gt;m&lt;/mml:mtext&gt;&lt;mml:mrow&gt;&lt;mml:mo&gt;−&lt;/mml:mo&gt;&lt;mml:mn&gt;2&lt;/mml:mn&gt;&lt;/mml:mrow&gt;&lt;/mml:msup&gt;&lt;/mml:mrow&gt;&lt;/mml:math&gt;&lt;inline-graphic xlink:href=\"nfad703eieqn3.gif\"&gt;&lt;/inline-graphic&gt;&lt;/inline-formula&gt;. neutral beam injection (NBI) heating was also applied during some configurations of the scan to create a density ramp and access high densities beyond the X2 ECRH cutoff. For the magnetic configurations, where the &lt;inline-formula&gt;\u0000&lt;tex-math&gt;&lt;?CDATA $5/5$?&gt;&lt;/tex-math&gt;&lt;mml:math overflow=\"scroll\"&gt;&lt;mml:mrow&gt;&lt;mml:mn&gt;5&lt;/mml:mn&gt;&lt;mml:mrow&gt;&lt;mml:mo&gt;/&lt;/mml:mo&gt;&lt;/mml:mrow&gt;&lt;mml:mn&gt;5&lt;/mml:mn&gt;&lt;/mml:mrow&gt;&lt;/mml:math&gt;&lt;inline-graphic xlink:href=\"nfad703eieqn4.gif\"&gt;&lt;/inline-graphic&gt;&lt;/inline-formula&gt; and &lt;inline-formula&gt;\u0000&lt;tex-math&gt;&lt;?CDATA $5/6$?&gt;&lt;/tex-math&gt;&lt;mml:math overflow=\"scroll\"&gt;&lt;mml:mrow&gt;&lt;mml:mn&gt;5&lt;/mml:mn&gt;&lt;mml:mrow&gt;&lt;mml:mo&gt;/&lt;/mml:mo&gt;&lt;/mml:mrow&gt;&lt;mml:mn&gt;6&lt;/mml:mn&gt;&lt;/mml:mrow&gt;&lt;/mml:math&gt;&lt;inline-graphic xlink:href=\"nfad703eieqn5.gif\"&gt;&lt;/inline-graphic&gt;&lt;/inline-formula&gt; island chains were moved closer to separatrix but remaining inside the last closed flux surface, the electron cyclotron emission shows that an electron temperature, &lt;inline-formula&gt;\u0000&lt;tex-math&gt;&lt;?CDATA $T_{mathrm e}$?&gt;&lt;/tex-math&gt;&lt;mml:math overflow=\"scroll\"&gt;&lt;mml:mrow&gt;&lt;mml:msub&gt;&lt;mml:mi&gt;T&lt;/mml:mi&gt;&lt;mml:mrow&gt;&lt;mml:mrow&gt;&lt;mml:mi mathvariant=\"normal\"&gt;e&lt;/mml:mi&gt;&lt;/mml:mrow&gt;&lt;/mml:mrow&gt;&lt;/mml:msub&gt;&lt;/mml:mrow&gt;&lt;/mml:math&gt;&lt;inline-graphic xlink:href=\"nfad703eieqn6.gif\"&gt;&lt;/inline-graphic&gt;&lt;/inline-formula&gt;, pedestal develops already during ECRH heated plasma buildup phase indicating a transport barrier, and the","PeriodicalId":19379,"journal":{"name":"Nuclear Fusion","volume":"31 1","pages":""},"PeriodicalIF":3.3,"publicationDate":"2024-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142212119","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}