Publications by Federico David Halpern

DIII-D research towards establishing the scientific basis for future fusion reactors

Olivier Sauter, Wilfred Anthony Cooper, Lorenzo Anton-Louis Talà, Terunobu Akiyama, Mario Ludovico Podesta, Dongbin Zhao, Zhixian Yan, Jeffrey Huang, Xin Yang, Richard Pitts

DIII-D research is addressing critical challenges in preparation for ITER and the next generation of fusion devices through focusing on plasma physics fundamentals that underpin key fusion goals, understanding the interaction of disparate core and boundary ...

IOP Publishing Ltd2019

Poloidal asymmetry in the narrow heat flux feature in the TCV scrape-off layer

Basil Duval, Christian Gabriel Theiler, Stefano Coda, Ivo Furno, Paolo Ricci, Holger Reimerdes, Benoît Labit, Joaquim Loizu Cisquella, Jan Horacek, Federico Nespoli

Heat flux profiles inferred from a reciprocating probe at the outer midplane of the TCV tokamak during inner wall limited discharges feature radial fall-off lengths that shorten near the last closed flux surface (LCFS) consistent with the so-called narrow ...

American Institute of Physics (AIP)2017

Blob properties in full-turbulence simulations of the TCV scrape-off layer

Ivo Furno, Paolo Ricci, Benoît Labit, Fabio Avino, Federico Nespoli, Federico David Halpern, Fabio Riva

To investigate blob properties in the tokamak scrape-off layer (SOL), we perform dedicated numerical nonlinear simulations of plasma turbulence in the SOL of a TCV discharge using the Global Braginskii Solver code. A blob detection technique is used for th ...

2017

Outer midplane scrape-off layer profiles and turbulence in simulations of Alcator C-Mod inner-wall limited discharges

Federico David Halpern

A region of steep plasma gradients, the so-called "narrow-feature," has been found in the near scrape-off layer (SOL) of inner-wall limited (IWL) discharges. Dedicated IWL discharges were carried out in Alcator C-Mod [Marmar et al., Nucl. Fusion 55, 104020 ...

Amer Inst Physics2017

Scrape-off-layer current loops and floating potential in limited tokamak plasmas

Paolo Ricci, Joaquim Loizu Cisquella, Paola Paruta, Federico David Halpern

We investigate the question of how plasma currents circulate and close in the scrape-off-layer (SOL) of convection-limited tokamak plasmas. A simplified two-fluid model describes how currents must evacuate charge at the sheaths due to cross-field currents ...

Cambridge University Press2017

Non-linear simulations of the TCV Scrape-Off Layer

Ivo Furno, Paolo Ricci, Benoît Labit, Joaquim Loizu Cisquella, Federico Nespoli, Federico David Halpern, Fabio Riva

To investigate the mechanisms leading to the heat deposition onto the first wall in the Scrape-Off Layer (SOL), we perform dedicated numerical non-linear simulations of the SOL plasma dynamics of a TCV discharge using the GBS code. The simulated parallel h ...

Elsevier Science Bv2017

Velocity shear, turbulent saturation, and steep plasma gradients in the scrape-off layer of inner-wall limited tokamaks

Paolo Ricci, Federico David Halpern

The narrow power decay-length (lambda(q)), recently found in the scrape-off layer (SOL) of inner-wall limited (IWL) discharges in tokamaks, is studied using 3D, flux-driven, global two-fluid turbulence simulations. The formation of the steep plasma profile ...

IOP Publishing Ltd2017

The GBS code for tokamak scrape-off layer simulations

Paolo Ricci, Joaquim Loizu Cisquella, Trach-Minh Tran, Sébastien Jolliet, Federico David Halpern, Fabio Riva, Annamaria Mosetto, Christoph Wersal

We describe a new version of GBS, a 3D global, flux-driven plasma turbulence code to simulate the turbulent dynamics in the tokamak scrape-off layer (SOL), superseding the code presented by Ricci et al. (2012) [14]. The present work is driven by the object ...

Elsevier2016

Neoclassical tearing mode seeding by coupling with infernal modes in low-shear tokamaks

Jonathan Graves, Wilfred Anthony Cooper, Federico David Halpern, Daniele Brunetti, Andreas Kleiner

A numerical and an analytical study of the triggering of resistive MHD modes in tokamak plasmas with low magnetic shear core is presented. Flat q profiles give rise to fast growing pressure driven MHD modes, such as infernal modes. It has been shown that i ...

IOP Publishing Ltd2016

A theoretical interpretation of the main scrape-off layer heat-flux width scaling for tokamak inner-wall limited plasmas

Paolo Ricci, Richard Pitts, Jan Horacek, Federico David Halpern

The International Tokamak Physics Activity Topical Group on scrape-off layer and divertor physics has amassed a database comprising hundreds of reciprocating Langmuir probe measurements of the main scrape-off layer heat-flux width lambda(q) in inner-wall l ...

Institute of Physics2016