Staircases in Confined Magnetized Plasmas — Overview via Selected Topics

Add to your list(s) Download to your calendar using vCal

• Patrick Diamond (University of California, San Diego)
• Thursday 18 January 2024, 09:00-10:00
• Seminar Room 1, Newton Institute.

If you have a question about this talk, please contact nobody.

ADIW01 - Layering — A structure formation mechanism in oceans, atmospheres, active fluids and plasmas

P. H. Diamond Depts. of Astronomy & Astrophysics and Physics U.C. San Diego This talk presents an overview of layering and staircases in confined magnetized plasmas, by way of a discussion of selected topics. Staircase formation due to inhomogeneous mixing of heat, particles, etc. is well known in confined plasmas. Many mechanisms of inhomogeneous mixings are possible, and will be critically discussed. Basic models of confined magnetized plasmas are introduced, with an emphasis on physical simplicity, and accessibility to a broad audience. Models of staircase formation are then discussed, with an emphasis on: i) Two-scale mixing, with one scale emergent. Transition from “staircase” to “transport barrier” states in these models are of particular interest. ii) Jam formation in avalanching. Confined plasmas of interest are typically heat flux driven, and thus support avalanches. Jams form in avalanching systems, then leading to staircase formation. More generally, the seemingly intimate relation between staircases and avalanches ‘near marginal stability’ is of some interest and will be discussed. iii) Self-sharpening, as in homogenization in an array of convective cells, which may be anisotropic (i.e. zonal flows). A state of a weakly fluctuating vortex array (“finite temperature vortex crystal”) is a particularly compelling venue in which to study layering by self-sharpening. Resiliency of self-sharpened staircase states will be discussed. We will also introduce key experimental results on staircases and discuss related mesoscopic phenomena, such as turbulence spreading. Additional systems with dynamics resembling those of plasmas (such as Cahn–Hilliard–Navier–Stokes) – and which manifest layering – will be discussed.

This talk is part of the Isaac Newton Institute Seminar Series series.

This talk is included in these lists:

• All CMS events
• Featured lists
• INI info aggregator
• Isaac Newton Institute Seminar Series
• School of Physical Sciences
• Seminar Room 1, Newton Institute
• bld31

Note that ex-directory lists are not shown.