Publications related to Gaussian surface

Parallel convection and E × B drifts in the TCV snowflake divertor and their effects on target heat-fluxes

Basil Duval, Holger Reimerdes, Joaquim Loizu Cisquella, Roberto Maurizio, Davide Galassi, Cedric Kar-Wai Tsui, Mirko Wensing

Parallel convection and E × B drifts act together to redistribute heat between the strike-points mechanisms is enhanced near the secondary X-point and is shown to dominate over heat in the low field side snowflake minus (LFS SF−). The cumulative heat conve ...

IOP Publishing Ltd2021

Coordinate parameterisation and spectral method optimisation for Beltrami field solver in stellarator geometry

David Pfefferlé, Aravind Kumar Chandiran, Antoine Baillod, Ajay Kumar

The numerical solution of the stepped pressure equilibrium (Hudson et al 2012 Phys. Plasmas 19 112502) requires a fast and robust solver to obtain the Beltrami field in three-dimensional geometry such as stellarators. The spectral method implemented in the ...

2020

Time-reversal symmetry breaking Abelian chiral spin liquid in Mott phases of three-component fermions on the triangular lattice

Frédéric Mila, Karlo Penc, Pierre Marcel Nataf, Miklos Lajko, Carolin Boos

We provide numerical evidence in favor of spontaneous chiral symmetry breaking and the concomitant appearance of an Abelian chiral spin liquid for three-component fermions on the triangular lattice described by an SU(3) symmetric Hubbard model with hopping ...

2020

The impact of anisotropy on ITER scenarios

Olivier Sauter

We report on the impact of anisotropy to tokamak plasma configuration and stability. Our focus is on analysis of the impact of anisotropy on ITER pre-fusion power operation 5 MA, B = 1.8 T ICRH scenarios. To model ITER scenarios remapping tools are develop ...

IOP Publishing Ltd2020

A Covariance Formula For Topological Events Of Smooth Gaussian Fields

Alejandro Rivera

We derive a covariance formula for the class of 'topological events' of smooth Gaussian fields on manifolds; these are events that depend only on the topology of the level sets of the field, for example, (i) crossing events for level or excursion sets, (ii ...

INST MATHEMATICAL STATISTICS2020

Manufacturing, installation, commissioning, and first results with the 3D low-temperature co-fired ceramic high-frequency magnetic sensors on the Tokamak a Configuration Variable

Duccio Testa

Innovative high-frequency magnetic sensors have been designed and manufactured in-house for installation on the Tokamak a Configuration Variable (TCV), which are now routinely operational during the TCV experimental campaigns. These sensors combine the Low ...

2020

Tokamak Edge Plasma Turbulence Interaction with Magnetic X-Point in 3D Global Simulations

Davide Galassi, Eric Serre

Turbulence in the edge plasma of a tokamak is a key actor in the determination of the confinement properties. The divertor configuration seems to be beneficial for confinement, suggesting an effect on turbulence of the particular magnetic geometry introduc ...

2019

Spatiotemporal dynamics of snow erosion, deposition and horizontal mass flux

Michael Lehning, Enrico Paterna, Philip Crivelli

The quantification of snow transport, both in wind tunnels and the field, apply particle counting methods limited to punctual sampling of relatively small volumes. Particle counting can only capture horizontal mass fluxes, failing to measure snow erosion o ...

2019

LTCC magnetic sensors at EPFL and TCV: Lessons learnt for ITER

Duccio Testa, Xavier Llobet, Pierre Lavanchy, Matthieu Toussaint, Ugo Siravo, Frédéric Dolizy, Jonathan Bryan Lister, Thomas Maeder, Steve Couturier, Philippe Marmillod, Severino Antonioni, Caroline Jacq, Christian Moura, Blaise Marlétaz, Aylwin Iantchenko, Lorenzo Stipani, Adrien Aymeric Thibault Corne, Matthias Garcin

Innovative 3D high-frequency magnetic sensors have been designed and manufactured in-house for installation on the Tokamak a Configuration Variable (TCV), and are currently routinely operational. These sensors combine the Low Temperature Co-fired Ceramic ( ...

2019

Decompositions Of Log-Correlated Fields With Applications

Janne Matias Junnila

In this article, we establish novel decompositions of Gaussian fields taking values in suitable spaces of generalized functions, and then use these decompositions to prove results about Gaussian multiplicative chaos. We prove two decomposition theorems. Th ...

2019

Energetic ion dynamics and confinement in 3D saturated MHD configurations

David Pfefferlé

In the following theoretical and numerically oriented work, a number of findings have been assembled. The newly devised VENUS-LEVIS code, designed to accurately solve the motion of energetic particles in the presence of 3D magnetic fields, relies on a non- ...

EPFL2015

Basic characterization of TORPEX electrostatic modes in closed field line configurations

Ambrogio Fasoli, Ivo Furno, Paolo Ricci, Fabio Avino, Sébastien Jolliet

Electrostatic coherent modes are studied in the TORPEX device [Fasoli et al., Plasma Phys. Controlled Fusion 52, 124020 (2010)], in closed flux surfaces. The accessibility to this magnetic geometry is provided by a current-carrying in-vessel toroidal condu ...

Amer Inst Physics2014

Ideal ballooning modes in the tokamak scrape-off layer

Paolo Ricci, Joaquim Loizu Cisquella, Sébastien Jolliet, Federico David Halpern, Annamaria Mosetto

A drift-reduced Braginskii fluid model is used to carry out a linear and non-linear study of ideal ballooning modes in the tokamak scrape-off layer. First, it is shown that the scrape-off layer finite connection length and boundary conditions modify the id ...

American Institute of Physics2013

Indirect measurement of poloidal rotation using inboard–outboard asymmetry of toroidal rotation and comparison with neoclassical predictions

Olivier Sauter, Basil Duval, Alexander Karpushov, Yanis Andrebe, Yann Camenen, Alessandro Bortolon, Lucia Isabel Federspiel

An alternative experimental spectroscopic measurement of poloidal plasma rotation in toroidally confined plasmas is proven effective in the TCV tokamak. Charge exchange recombination measurements of the toroidal rotation profile over the full mid-plane pla ...

Int Atomic Energy Agency2012

Progress on the ITER ECRH upper launcher steering mirror identification and control

René Chavan, Federico Alberto Alfredo Felici, Jean-Daniel Landis, Frédéric Dolizy, Francisco Sanchez, Robert Bertizzolo

The main objective of the ITER ECRH upper launcher (UL) is to control magnetohydrodynamic activity, in particular neoclassical tearing modes (NTMs), by driving several MW of EC Current near the q = 1, 3/2, 2 flux surfaces, where NTMs are expected to occur. ...

Elsevier2009

Three-dimensional anisotropic pressure free boundary equilibria

Wilfred Anthony Cooper, Jonathan Graves

Free boundary three-dimensional anisotropic pressure magnetohydrodynamic equilibria with nested magnetic flux surfaces are computed through the minimisation of the plasma energy functional

W={\int}_{V}{d^3}x\left[{B^2}/(2\mu_0)+p_{||}/(\Gamma-1)\right]

. ...

2009

On the coupling integrals arising in the method of moments formulation of laterally bounded structures

Juan Ramon Mosig, Ivica Stevanovic, Pedro Crespo Valero

A generic integral equation and method of moments formulation is presented for laterally bounded stratified media including planar metallization. The main asset of the developed approach is its flexibility, as it encompasses generic lateral boundary condit ...

Institute of Electrical and Electronics Engineers2008

The surface Laplacian operator of the potentials on a bounded volume conductor has a unique inverse

In the discussion on the use of the surface Laplacian (SL) of the distribution of bioelectric potentials on the body surface, the question remained open whether a complete specification of the SL of the potential over the surface bounding a volume conducto ...

2006

Anisotropic pressure bi-Maxwellian distribution function model for three-dimensional equilibria

Wilfred Anthony Cooper, Jonathan Graves

A formulation of the anisotropic pressure magnetohydrodynamic equilibrium problem for three-dimensional plasmas with imposed nested magnetic surfaces is developed based on a bi-Maxwellian model of the distribution function for the energetic particle specie ...

IOP Publishing Ltd2006

ELMS and strike point jumps

Duccio Testa, Richard Pitts

If an ELM is a peeling of flux surfaces from the plasma, due to a broken separatrix, current density is lost as well as particles and energy. The fast loss of a current-carrying plasma layer modifies the plasma equilibrium, leading to sudden shifts in the ...

2005