Events at Physics |
Events on Monday, March 11th, 2024
- Plasma Physics (Physics/ECE/NE 922) Seminar
- "Advances in optimization for stellarator design"
- Time: 12:00 pm - 1:15 pm
- Place: 1227 Engineering Hall
- Speaker: Elizabeth Paul, Columbia University
- Abstract: The immense freedom in the stellarator design space provides opportunities for reducing engineering complexity and improving confinement. This talk will provide an overview of recent advances in stellarator optimization and their application to the design of new experiments in the Columbia Plasma Laboratory. Recently, “precisely quasisymmetric” configurations have been obtained, demonstrating excellent confinement of fusion-born alpha particles in the absence of perturbations. There is, however, the potential for enhanced alpha losses due to resonant wave-particle interactions. We present pathways to model and optimize the alpha transport driven by Alfvenic instabilities through modification of the resonance structure and shear Alfven continuum. Furthermore, we discuss the incorporation of engineering constraints, including HTS strain and remote maintenance compatibility, into the stellarator design process. The Columbia Plasma Laboratory will validate these advances. The Columbia Stellarator eXperiment (CSX) will build on the success of the Columbia Non-neutral Torus (CNT) to confine a small aspect ratio quasisymmetric plasma with two shaped interlinked coils. Using this device, we will explore the physics of quasiaxisymmetry and demonstrate non-insulated HTS technology for non-planar magnets.
- Host: Prof. Carl Sovinec and Prof. Chris Hegna
- Department Meeting
- Closed Department Meeting
- Time: 12:15 pm - 1:15 pm
- Place: B343 Sterling Hall
- Speaker: Mark Eriksson, UW - Madison
- Host: Mark Eriksson
- Plasma Seminar
- Structuring Light: The Next Frontier in Laser-Plasma Interactions
- Time: 3:30 pm - 4:30 pm
- Place: B343 Sterling Hall
- Speaker: Andrew Longman, Lawrence Livermore National Lab
- Abstract: Recently, orbital angular momentum (OAM) beams have demonstrated at relativistic intensities at several high-power laser facilities around the world using off-axis spiral phase mirrors. The additional angular momentum carried by OAM beams, even when linearly polarized, introduces a new control parameter in laser plasma interactions and has shown promise to introduce new and exciting phenomena not possible with a standard Gaussian beam. Of particular interest to this seminar is the relativistic inverse Faraday effect where laser angular momentum is absorbed by a plasma generating large axial magnetic fields colinear with the laser k vector. Our recent work has demonstrated that magnetic fields on the order of 100’s of Tesla, extending 100’s of microns, and lasting on the order of 10 picoseconds can be generated with laser powers less than 5 terawatts. I will present results from a recent campaign at the COMET laser at Lawrence Livermore National Laboratory in which we used a linearly polarized Laguerre Gaussian laser to drive magnetic fields for the first time in the laboratory. Experimental results will be compared and validated against theory and simulations.
- Host: Jan Egedal