124 citations · 576 across the 23 of their papers we have counts for
24 papers
Role of the radial electric field in the confinement of energetic ions in the Wendelstein 7-X stellarator
M. Arranz, J. L. Velasco, I. Calvo +1
Good fast-ion confinement is an essential requirement for a fusion reactor. The magnetic configuration of the Wendelstein 7-X (W7-X) stellarator is partially optimized in this rega…
A feasibility study for a Doppler Reflectometer System in the JT-60SA tokamak
D. Carralero, T. Happel, T. Estrada +5
In this work we present a study on the viability and practicality of installing a Doppler reflectometer (DR) system in the JT-60SA advanced tokamak. First, we discuss its scientifi…
Piecewise omnigenous magnetohydrodynamic equilibria as fusion reactor candidates
V. Fernández-Pacheco, J. L. Velasco, E. Sánchez +5
In piecewise omnigenous magnetic fields, charged particles remain perfectly confined in the abscence of collisions and turbulence. This concept extends the traditional notion of om…
Impact of magnetic islands on plasma flow and turbulence in W7-X
T. Estrada, E. Maragkoudakis, D. Carralero +13
The effect of magnetic islands on plasma flow and turbulence has been experimentally investigated in the stellarator W7-X. Magnetic configurations with the 5/5 magnetic island posi…
Radial electric field and density fluctuations measured by Doppler reflectometry during the post-pellet enhanced confinement phase in W7-X
T. Estrada, D. Carralero, T. Windisch +13
Radial profiles of density fluctuations and radial electric field, , have been measured using Doppler reflectometry during the post-pellet enhanced confinement phase achieved,…
Validation of a Comprehensive First-Principles-Based Framework for Predicting the Performance of Future Stellarators
D. L. C. Agapito Fernando, A. Bañón Navarro, D. Carralero +20
This paper presents the validation of the framework for recovering both the steady-state plasma profiles in the considered radial domain and selected t…
First experimental observation of zonal flows in the optimized stellarator Wendelstein 7-X
D. Carralero, T. Estrada, J. M. García-Regaña +10
In this work, we present the first experimental evidence of the presence of zonal flow (ZF) structures in the optimized stellarator Wendelstein 7-X. Using an assortment of diagnost…
Electrostatic microturbulence in W7-X: comparison of local gyrokinetic simulations with Doppler reflectometry measurements
A. González-Jerez, J. M. García-Regaña, I. Calvo +5
The first experimental campaigns of Wendelstein 7-X (W7-X) have shown that turbulence plays a decisive role in the performance of neoclassically optimized stellarators. This stress…
On the interaction between the island divertor heat fluxes, the scrape-off layer radial electric field and the edge turbulence in Wendelstein 7-X plasmas
E. Maragkoudakis, D. Carralero, T. Estrada +11
The formation of the radial electric field, in the SOL has been experimentally studied for attached divertor conditions in stellarator W7-X. The main objective of this…
On the role of density fluctuations in the core turbulent transport of Wendelstein 7-X
D. Carralero, T. Estrada, E. Maragkoudakis +19
A recent characterization of core turbulence carried out with a Doppler reflectometer in the optimized stellarator Wendelstein 7-X (W7-X) found that discharges achieving high ion t…
Physics design point of high-field stellarator reactors
J. A. Alonso, I. Calvo, D. Carralero +4
The ongoing development of electromagnets based on High Temperature Superconductors has led to the conceptual exploration of high-magnetic-field fusion reactors of the tokamak type…
Fast simulations for large aspect ratio stellarators with the neoclassical code KNOSOS
J. L. Velasco, I. Calvo, F. I. Parra +5
In this work, a new version of KNOSOS is presented. KNOSOS is a low-collisionality radially-local, bounce-averaged neoclassical code that is extremely fast, and at the same time, i…
An experimental characterization of core turbulence regimes in Wendelstein 7-X
D. Carralero, T. Estrada, E. Maragkoudakis +14
First results from the optimized helias Wendelstein 7-X stellarator (W7-X) have shown that core transport is no longer mostly neoclassical, as is the case in previous kinds of stel…
Characterization of the radial electric field and edge velocity shear in Wendelstein 7-X
D. Carralero, T. Estrada, T. Windisch +13
In this work we present the first measurements obtained by the V-band Doppler reflectometer during the second operation phase of Wendelstein 7-X to discuss the influence in the vel…
Recent progress towards a quantitative description of filamentary SOL transport
D. Carralero, M. Siccinio, M. Komm +22
A summary of recent results on filamentary transport, mostly obtained in the ASDEX-Upgrade tokamak (AUG), is presented and discussed in an attempt to produce a coherent picture of…
On the role of filaments in perpendicular heat transport at the Scrape-off Layer
D. Carralero, S. Artene, M. Bernert +9
In this work we carry out quantitative measurements of particle and heat transport associated to SOL filaments in a tokamak, and relate density shoulder formation to the advection…
Heat and particle flux detachment with stable plasma conditions in the Wendelstein 7-X stellarator fusion experiment
Marcin Jakubowski, Ralf König, Oliver Schmitz +30
Reduction of particle and heat fluxes to plasma facing components is critical to achieve stable conditions for both the plasma and the plasma material interface in magnetic confine…
Global scaling of the heat transport in fusion plasmas
Sara Moradi, Johan Anderson, Michele Romanelli +2
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 he…
On-surface potential and radial electric field variations in electron root stellarator plasmas
J. M. García-Regaña, T. Estrada, I. Calvo +8
In the present work we report recent radial electric field measurements carried out with the Doppler reflectometry system in the TJ-II stellarator. The study focuses on the fact th…
ExB analyzer for fast ion temperature measurements in scrape-off layer of the ASDEX Upgrade and COMPASS tokamaks
M. Komm, M. Kocan, D. Carralero +3
Ion temperature in the scrape-off layer is an important quantity but rarely measured at high temporal resolution. In order to achieve fast measurements during intermittent events s…
Experimental validation of a filament transport model in turbulent magnetized plasmas
D. Carralero, P. Manz, L. Aho-Mantila +9
In a wide variety of natural and laboratory magnetized plasmas, filaments appear as a result of interchange instability. These convective structures substantially enhance transport…
An experimental investigation on the high density transition of the Scrape-off Layer transport in ASDEX Upgrade
D. Carralero, G. Birkenmeier, H. W. Müller +8
A multidiagnostic approach, utilizing Langmuir probes in the midplane, X-point and divertor walls, along with Lithium beam and infrared measurements is employed to evaluate the evo…
Dynamics of zonal flow-like structures in the edge of the TJ-II stellarator
J. A. Alonso, J. L. Velasco, J. Arévalo +4
The dynamics of fluctuating electric field structures in the edge of the TJ-II stellarator, that display zonal flow-like traits, is studied. These structures have been shown to be…
Dynamic transport regulation by zonal flow-like structures in the TJ-II stellarator
J. A. Alonso, C. Hidalgo, M. A. Pedrosa +3
Floating potential structures that are correlated over a long distance are observed with a 2D probe array in the plasma edge of the TJ-II stellarator. We introduce a method based o…