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Concept

Ionosphere

Related publications (26)

Iterative removal of sources to model the turbulent electromotive force

Salim Bennouna, Abhijit Bhausaheb Bendre

We describe a novel method to compute the components of dynamo tensors from direct magnetohydrodynamic (MHD) simulations. Our method relies upon an extension and generalization of the standard H & ouml;gbom CLEAN algorithm widely used in radio astronomy to ...

Oxford Univ Press2024

Ionospheric Variations Induced by Thunderstorms in the Central Region of Argentina during the RELAMPAGO–CACTI Campaign

Farhad Rachidi-Haeri, Marcos Rubinstein

The ionosphere can be perturbed by solar and geomagnetic activity, earthquakes, thunderstorms, etc. In particular, electromagnetic pulses produced by thunderstorms can generate wave structures in the ionospheric plasma, which are known as atmospheric gravi ...

2023

Lightning interaction with the ionosphere

Farhad Rachidi-Haeri, Marcos Rubinstein

Lightning discharges, including cloud-to-ground (CG) and intracloud (IC) lightning, are known to emit electromagnetic pulses (EMPs) in a wide frequency band ranging from few Hz up to hundreds MHz [1]. During the breakdown and ionization processes (mostly f ...

IET2023

Small-scale dynamo with finite correlation times

Salim Bennouna

Fluctuation dynamos occur in most turbulent plasmas in astrophysics and are the prime candidates for amplifying and maintaining cosmic magnetic fields. A few analytical models exist to describe their behavior, but they are based on simplifying assumptions. ...

AMER PHYSICAL SOC2023

Model-based impurity emission front control using deuterium fueling and nitrogen seeding in TCV

Basil Duval, Christian Gabriel Theiler, Cristian Galperti, Artur Perek

This paper presents the first result using nitrogen-seeded exhaust feedback control of the NII impurity emission front in TCV. The NII emission front position is consistently located below its commonly used CIII counterpart, indicating the NII emission fro ...

IOP Publishing Ltd2023

Investigation of the effects of the Greek extreme wildfires of August 2021 on air quality and spectral solar irradiance

Alexandros Papagiannis

In August 2021, a historic heatwave was recorded in Greece which resulted in extreme wildfire events that strongly affected the air quality over the city of Athens. Saharan dust was also transferred over Greece on certain days of the same period due to the ...

Copernicus Publications2023

Numerical tools for burning plasmas

Laurent Villard, Jonathan Graves, Alberto Bottino, Ben McMillan, Emmanuel Lanti, Baruch Rofman

The software stack under development within a European coordinated effort on tools for burning plasma modelling is presented. The project is organised as a Task (TSVV Task 10) under the new E-TASC initiative (Litaudon et al 2022 Plasma Phys. Control. Fusio ...

IOP Publishing Ltd2023

Dynamo instabilities in plasmas with inhomogeneous chiral chemical potential

Salim Bennouna

We study the dynamics of magnetic fields in chiral magnetohydrodynamics, which takes into account the effects of an additional electric current related to the chiral magnetic effect in high-energy plasmas. We perform direct numerical simulations, consideri ...

American Physical Society2022

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

Farhad Rachidi-Haeri, Marcos Rubinstein, Mohammad Azadifar

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

Farhad Rachidi-Haeri, Marcos Rubinstein, Davide Pavanello, Mohammad Azadifar, Amirhossein Mostajabi

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 ...

Elsevier2019

Numerical investigation of the mixed-mode failure of snow

Johan Alexandre Philippe Gaume

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, Martinus Adela Maria Gijs, Jonathan Graves, Ambrogio Fasoli, Stefano Coda, Basil Duval, Henri Weisen, Richard Pitts, Yves Martin, Javier García Hernández, Duccio Testa, Miguel Fernández Ruiz, Nicola Vianello, Robin Humphry-Baker, Sun Hee Kim, Federico Nespoli, Patrick Blanchard, Alessandro Pau, David Pfefferlé, Davide Galassi, Jonathan Marc Philippe Faustin, Cristian Sommariva, Hamish William Patten, Samuel Lanthaler, Jan Horacek, Yann Camenen, Bruno Emanuel Ferreira De Sousa Correia, José Pedro Rebelo Ferreira Marques, Mikhail Maslov, Marco Wischmeier, Dalziel Joseph Wilson, Liang Yao, Daniel Scott Alessi, Arnout Lodewijk M Beckers, Ana Francisca Leal Silva Soares, Jonnathan Cesar Hidalgo Acosta, Antonio José Pereira de Figueiredo, Partha Dutta, Pierre-Thomas Paul Brun, Pedro Camilo de Oliveira e Silva, Alberto Hernando de Castro, Julio Rodriguez, Vlad Trifa, Li Shuai, Rebecca Hill

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

Light impurity transport in JET ILW L-mode plasmas

A series of experimental observations of light impurity profiles was carried out in JET (Joint European Torus) ITER-like wall (ILW) L-mode plasmas in order to investigate their transport mechanisms. These discharges feature the presence of He-3, Be, C, N, ...

IOP Publishing Ltd2018

Analysis of lightning-ionosphere interaction using simultaneous records of source current and 380 km distant electric field

Farhad Rachidi-Haeri, Marcos Rubinstein, Mario Paolone, Davide Pavanello, Mohammad Azadifar

We present simultaneous current and wideband electric field waveforms at 380 km associated with upward lightning flashes initiated from the Santis Tower, Switzerland. To the best of our knowledge, the dataset presented in this study includes the first simu ...

Elsevier2017

A drift-kinetic analytical model for scrape-off layer plasma dynamics at arbitrary collisionality

Paolo Ricci, Rogério Manuel Cabete De Jesus Jorge

A drift-kinetic model to describe the plasma dynamics in the scrape-off layer region of tokamak devices at arbitrary collisionality is derived. Our formulation is based on a gyroaveraged Lagrangian description of the charged particle motion, and the corres ...

Cambridge University Press2017

Detachment evolution on the TCV tokamak

Basil Duval, Holger Reimerdes, Marco Wischmeier, Benoît Labit, Christian Gabriel Theiler, Umar Sheikh, Cedric Kar-Wai Tsui, Wouter Vijvers, Kevin Henricus Annemarie Verhaegh

Divertor detachment in the TCV tokamak has been investigated through experiments and modelling. Density ramp experiments were carried out in ohmic heated L-mode pulses with the ion del B drift directed away from the primary X-point, similar to previous stu ...

Elsevier2017

Impact of neutral density fluctuations on gas puff imaging diagnostics

Paolo Ricci, Christoph Wersal

A three-dimensional turbulence simulation of the SOL and edge regions of a toroidally limited tokamak is carried out. The simulation couples self-consistently the drift-reduced two-fluid Braginskii equations to a kinetic equation for neutral atoms. A diagn ...

International Atomic Energy Agency2017