Concept

Ionosphere

Related publications (65)

Impact of the new TCV baffled divertor upgrade on pedestal structure and performance

Basil Duval, Patrick Blanchard, Holger Reimerdes, Benoît Labit, Christian Gabriel Theiler, Antoine Pierre Emmanuel Alexis Merle, Umar Sheikh, Davide Galassi

A new set of carbon tiles, neutral beam heating optics and gas baffles were installed on TCV during thebaffled divertor upgrade in early 2019. The installation of the baffles allows a deconvolution of the roles ofmain chamber and divertor neutral pressure ...

2021

Beam duct for the 1 MW neutral beam injector on TCV

Basil Duval, Stefano Coda, Yves Martin, Alexander Karpushov, Matthieu Toussaint, Frédéric Dolizy, Roberto Maurizio

The 1MW power of the neutral beam injector (NBI) enters the plasma of the Tokamak a Configuration Variable (TCV) through a duct. The original beam propagation model predicted a maximal heat flux on the internal faces of the duct below 350 kW/m(2), leading ...

2020

Low-loss SiN waveguides for efficient and broadly tunable nonlinear frequency conversion

Tobias Kippenberg, Camille Sophie Brès, Junqiu Liu, Florent Gilles Mazeas

We report on the use of low-loss Si3N4 waveguides for efficient frequency conversion tunable from the near infrared to the short-wave infrared. We achieve -15 dB conversion efficiency for 200 mW coupled pump power. ...

2020

The Propagation Effects of Lightning Electromagnetic Fields Over Mountainous Terrain in the Earth-Ionosphere Waveguide

Marcos Rubinstein, Mohammad Azadifar, Dongshuai Li

In this paper, a full-wave two-dimensional Finite-Difference-Time-Domain model is developed to evaluate the propagation effects of lightning electromagnetic fields over mountainous terrain in the Earth-ionosphere waveguide. In the model, we investigate the ...

2019

Analysis of a bipolar upward lightning flash based on simultaneous records of currents and 380-km distant electric fields

Marcos Rubinstein, Mohammad Azadifar, Amirhossein Mostajabi, Wolfgang Schulz, Davide Pavanello, Dongshuai Li

In this paper, we present and discuss simultaneous records of current and wideband electric field waveforms at 380 km distance from the strike point associated with an upward bipolar flash initiated from the Säntis Tower. The flash contains 23 negative str ...

2019

Numerical investigation of the mixed-mode failure of snow

Johan Alexandre Philippe Gaume, Dominika Mulak

The failure of a weak snow layer underlying a cohesive slab is the primary step in the release process of a dry snow slab avalanche. The complex and heterogeneous microstructure of snow limits our understanding of failure initiation inside the weak layer, ...

2019

Characteristics of Upward Lightning Flashes

Mohammad Azadifar

In addition to the general aims of lightning research such as lightning physics and meteorology, the study of upward lightning is of particular importance in protection of tall objects such as wind turbines and telecommunication towers. It also helps us in ...

EPFL2018

Sub-millisecond electron density profile measurement at the JET tokamak with the fast lithium beam emission spectroscopy system

Olivier Sauter, Ambrogio Fasoli, Basil Duval, Stefano Coda, Jonathan Graves, Yves Martin, Duccio Testa, Patrick Blanchard, Alessandro Pau, Cristian Sommariva, Henri Weisen, Richard Pitts, Yann Camenen, Jan Horacek, Javier García Hernández, Marco Wischmeier, Nicola Vianello, Mikhail Maslov, Federico Nespoli, Yao Zhou, David Pfefferlé, Davide Galassi, Antonio José Pereira de Figueiredo, Jonathan Marc Philippe Faustin, Liang Yao, Dalziel Joseph Wilson, Hamish William Patten, Samuel Lanthaler, Bernhard Sieglin, Otto Asunta

Diagnostic alkali atom (e.g., lithium) beams are routinely used to diagnose magnetically confined plasmas, namely, to measure the plasma electron density profile in the edge and the scrape off layer region. A light splitting optics system was installed int ...

2018

Extreme Values of Lightning Parameters

Marcos Rubinstein, Aleksandr Smorgonskii

In this paper we present an online database where we have collected a number of reports on extreme lightning parameters: peak current, fastest and slowest rise time, fastest and slowest time to half value, rate of change of current, flash duration, charge ...

2018

Correlation of surface chemical states with hydrogen isotope retention in divertor tiles of JET with ITER-Like Wall

To understand the fuel retention mechanism correlation of surface chemical states and hydrogen isotope retention behavior determined by XPS (X-ray photoelectron spectroscopy) and TDS (Thermal desorption spectroscopy), respectively, for JET ITER-Like Wall s ...

ELSEVIER SCIENCE SA2018

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