Validating the ASCOT modelling of NBI fast ions in Wendelstein 7-X stellarator

  title={Validating the ASCOT modelling of NBI fast ions in Wendelstein 7-X stellarator},
  author={Simppa {\"A}k{\"a}slompolo and Peter Drewelow and Y. Gao and A. Ali and Christoph Biedermann and Sergey Bozhenkov and Chandra Prakash Dhard and Michael Endler and Joris H. H. Fellinger and Oliver P. Ford and Benedikt Geiger and Joachim Geiger and N den Harder and Dirk Hartmann and Dag Hathiramani and Mitsutaka Isobe and Marcin W. Jakubowski and Yevgen Kazakov and Carsten Killer and Samuel Aaron Lazerson and Matej Mayer and Paul McNeely and Dirk Naujoks and T. W. C. Neelis and J. Kontula and Taina Kurki-Suonio and Helge Niemann and Kunihiro Ogawa and Fabio Pisano and Peter Zs. Poloskei and Aleix Puig Sitjes and Kian Rahbarnia and N. J. A. Rust and John C. Schmitt and Marcin Ślęczka and Lilla Van{\'o} and Anton Jansen van Vuuren and Glen Anthony Wurden and Robert C. Wolf},
  journal={Journal of Instrumentation},
  pages={C10012 - C10012}
The first fast ion experiments in Wendelstein 7-X were performed in 2018. They are one of the first steps in demonstrating the optimised fast ion confinement of the stellarator. The fast ions were produced with a neutral beam injection (NBI) system and detected with infrared cameras (IR), a fast ion loss detector (FILD), fast ion charge exchange spectroscopy (FIDA), and post-mortem analysis of plasma facing components. The fast ion distribution function in the plasma and at the wall is being… 

Figures from this paper

First neutral beam experiments on Wendelstein 7-X

In the previous divertor campaign, the Wendelstein 7-X (W7-X) device injected 3.6 MW of neutral beam heating power allowing for the achievement of densities approaching 2 × 1020 m−3, and providing

Feasibility of neutral particle analysis for fast-ion measurements at W7-X

A preliminary study investigating capabilities of a planned but not yet installed neutral particle analyzer (NPA) [1,2] system combined with a diagnostic neutral beam at Wendelstein 7-X (W7-X) [3] is

Simulating the impact of charge exchange on beam ions in MAST-U

A model for simulating charge exchange (CX) of fast ions with background atoms in magnetically confined fusion plasmas has been implemented in the ASCOT orbit-following code. The model was verified

Plasma flow measurements based on charge exchange recombination spectroscopy in the Wendelstein 7-X stellarator

The initial operation of neutral beams in Wendelstein 7-X enabled the first measurements of carbon (C6+) temperature and rotation with a multi-chord charge exchange recombination spectroscopy system.

Characterization of correlations of fast-ion H-alpha measurement volumes in Wendelstein 7-X by particle tracking.

This paper characterizes the correlation of simultaneous measurements with different fast-ion H-alpha (FIDA) spectroscopy sightlines on Wendelstein 7-X. Using a collisionless guiding-center code, it

ASCOT simulations of 14 MeV neutron rates in W7-X: effect of magnetic configuration

Neutron production rates in fusion devices are determined not only by the kinetic profiles but also the fast ion slowing-down distributions. In this work, we investigate the effect of magnetic

A model for the fast evaluation of prompt losses of energetic ions in stellarators

A model is developed that, based on the radially-local bounce-averaged drift-kinetic equation, classifies orbits and succeeds in predicting configuration-dependent aspects of the prompt losses of energetic ions in stellarators.

Reciprocating probe measurements in the test divertor operation phase of Wendelstein 7-X

Reciprocating probes are a classic and widespread tool for the investigation of the edge and Scrape-Off Layer of magnetic fusion plasmas. In the Wendelstein 7-X (W7-X) stellarator, the Multi-Purpose

Operation of W7-X With an Inertially Cooled Divertor—On the Way to Steady State Operation

The superconducting stellarator Wendelstein 7-X has completed the first three experimental phases, the first one with a limiter only and two phases with an inertially cooled carbon divertor

ASCOT simulations of W7-X neutron rates: effect of magnetic configuration

Demonstrating improved confinement of energetic ions is one of the key goals of the Wendelstein 7-X (W7-X) stellarator. In the past campaigns, measuring confined fast ions has proven to be



Validating fast-ion wall-load IR analysis-methods against W7-X NBI empty-torus experiment

The first neutral beam injection (NBI) experiments in Wendelstein 7-X (W7-X) stellarator were conducted in the summer of 2018. The NBI system is used to heat the magnetically confined plasma by

Performance of Wendelstein 7-X stellarator plasmas during the first divertor operation phase

Wendelstein 7-X is the first comprehensively optimized stellarator aiming at good confinement with plasma parameters relevant to a future stellarator power plant. Plasma operation started in 2015

A Code that Simulates Fast-Ion D(alpha) and Neutral Particle Measurements

A code that models signals produced by charge-exchange reactions between fast ions and injected neutral beams in tokamak plasmas is described. With the fast- ion distribution function as input, the

Modelling neutral beams in fusion devices: Beamlet-based model for fast particle simulations

ASCOT: Solving the kinetic equation of minority particle species in tokamak plasmas

Neoclassical transport simulations for stellarators

The benchmarking of the thermal neoclassical transport coefficients is described using examples of the Large Helical Device (LHD) and TJ-II stellarators. The thermal coefficients are evaluated by

Infrared imaging systems for wall protection in the W7-X stellarator (invited).

In the upcoming experimental campaign, a graphite scraper element, in front of the island divertor throat, will be tested as a possible means to protect the divertor pumping gap edges during the transient discharge evolution.

V3FIT: a code for three-dimensional equilibrium reconstruction

The V3FIT code for performing equilibrium reconstruction in three-dimensional plasmas is described. It is a modular code that has the potential to be coupled with a variety of equilibrium solvers to

Energy and pitch angle resolved escaping beam ion measurement by Faraday-cup-based fast ion loss detector in Wendelstein 7-X, 2019 JINST 14 C09021

  • 2019