Abstracts

Siddharth Bachoti, Auburn University

Title: Interplay of dust ordering and potential structures in magnetized low temperature plasmas

Abstract: TBD

Tervor Bowen, UC Berkeley

Title: TBD

Abstract: TBD

Michael Churchill, PPPL

Title: TBD

Abstract: TBD

Seth Dorfman, Space Science Institute

Title: TBD

Abstract: TBD

Alessandro Geraldini, EPFL SPC

Title: Characteristics and constraints of plasma sheaths at shallow magnetic field incidence

Abstract: Just like all laboratory plasmas, the plasma in a fusion device is intertwined with its solid boundaries. Far away from the walls, transport is successfully described and simulated by fluid or kinetic models which average over the quasi-circular Larmor orbits of charged particles, and solve for the electric field via quasineutrality. Turbulence in the edge region has emerged as crucial in determining the overall confinement in the device, and the wall ultimately sets the boundary conditions. Yet, due to the typically grazing incident angle of the magnetic field lines, ion gyro-orbits deform to non-circular in a region near the wall called the magnetic presheath, as the electric field directed towards the target becomes so large and inhomogeneous, at the gyro-radius length scale, that it causes sheared ExB flows tangential to the target of the order of the thermal velocity.

In order to reflect electrons and keep the outflow ambipolar, the electric field even closer to the target, within the actual Debye sheath, becomes inhomogeneous on the scale of the Debye length, thus breaking quasineutrality and possibly also deforming electron gyro-orbits. I will present a theoretical framework and a numerical scheme that allow to iteratively and quickly obtain numerical solutions of the steady state of the magnetised plasma sheath (Debye sheath + magnetic presheath) for shallow magnetic field incidence at the wall, relevant to fusion devices. The code also returns the ion distribution function reaching the target, important for sputtering, and the reflected electron distribution function, which determines the net electron fluxes to the wall. I will also outline the necessary conditions for a monotonic and steady-state sheath solution to exist, and discuss the possible implications of the nontrivial constraints that emerge when gradients tangential to the target affect transport to the wall.

Renaud Gueroult, CNRS

Title: TBD

Abstract: TBD

Yashika Ghai, ORNL

Title: TBD

Abstract: TBD

Armand Keyhani, University of Wisconsin-Madison

Title: Anomalous Ion Heating in Ultra-Low Safety-Factor Toroidal Pinch Plasmas

Abstract: TBD

Ripudaman Singh Nirwan, West Virginia University

Title: Reconnection-Driven Electron Acceleration

Abstract: Magnetic reconnection converts the magnetic energy available in a plasma to the kinetic energy of its constituent particles. In the simplest case, it occurs between anti-parallel magnetic field lines meeting in a plane. A more general variant known as 'component reconnection' involves field lines reconnecting at an angle, giving a non-zero magnetic field component perpendicular to the plane of reconnection. This component is known as the 'guide field' and it is normalised to the reconnecting component. It controls the particle-scale dynamics of reconnection and influences the ensuing particle acceleration.

Component reconnection occurs in the Earth's magnetosphere, along with a variant known as 'electron-only' reconnection which precludes ion dynamics. West Virginia University's PHAse Space MApping (PHASMA) experiment can generate electron-only reconnection with a variable guide field. We have used this platform to study electron acceleration along the local magnetic field as a function of the guide field and found that electron acceleration is enhanced as the guide field is reduced. This occurs with the formation of non-thermal electron energy distribution functions (EEDFs) whose peak energies increase as the guide field decreases. A cross-over occurs at a guide field of 10, when the spatio-temporal production of energetic electrons in PHASMA increases dramatically. Measurements for this case reveal the production of a non-thermal, multi-component EEDF in conjunction with bulk electron heating along the local magnetic field.

Byonghoon Seo, Embry-Riddle Aeronautical University

Title: TBD

Abstract: TBD

Ricardo Shousha, PPPL

Title: Artificial intelligence for modeling and control of complex magnetized plasma systems

Authors: R. Shousha, P. Steiner, A. Jalalvand, J. Seo, S.K. Kim, K. Erickson, A. Rothstein, H. Farre, C. Byun, M.S. Kim and E. Kolemen

Abstract: Magnetized plasma systems, such as those in fusion devices, are challenging to model and control because of their nonlinear behavior, coupled physical processes, and diagnostic limitations. Traditional physics-based methods often lack the flexibility or computational efficiency required for real-time scenarios, restricting predictive accuracy and control performance. Recent advances in artificial intelligence have allowed us to address some of these limitations. For example, real-time tokamak plasma state-estimation frameworks (e.g., RTCAKENN[1]) predict multiple plasma profiles—including electron density, temperature, pressure, current density, safety factor, ion temperature, and toroidal rotation—even under conditions of diagnostic sparsity. AI-enhanced spectroscopic techniques further enable ion profile determination from relatively simple measurements, reducing the need for costly or less robust neutral beams. Additionally, AI-based super-resolution approaches infer high-fidelity data by leveraging correlations among multiple diagnostics, offering new insights into phenomena such as ELMs and magnetic island formation. Deep reinforcement learning and other machine learning–driven strategies have also demonstrated improved control of plasma instabilities, including tearing mode avoidance[2], and the optimization of actuator configurations for ELM suppression in devices such as KSTAR and DIII-D[3]. These developments indicate that AI-based approaches, demonstrated in the context of tokamak modeling and control, may hold potential for broader application across magnetized plasma systems as well.

References:
[1] Ricardo Shousha et al 2024 Nucl. Fusion 64 026006
[2] Jaemin Seo et al.. Nature 626, 746–751 (2024)
[3] SangKyeun Kim et al Nat Commun 15, 3990 (2024)

Sanat Tiwari, Indian Institute of Technology, Jammu

Title: TBD

Abstract: TBD

Luca Vialetto, Stanford University

Title: TBD

Abstract: TBD