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February 9, 2016

February 9, 2016

December 3, 2015

Submission Instructions

Submission Template

February 20, 2013
Prospects for IFE Report

Assessment of Inertial Confinement Fusion Targets Report

New Beam Emission Spectroscopy system on the NSTX:  The diagnostic development research group at the University of Wisconsin has recently obtained first measurements of long-wavelength density fluctuations in the NSTX spherical torus with a newly deployed Beam Emission Spectroscopy (BES) system. The NSTX-BES system has demonstrated very high signal-to-noise performance, allowing for detailed, time-resolved investigation of fluctuations associated with turbulence, energetic particle-driven modes including global Alfven eigenmodes (GAE), and pedestal characteristics. The system has been operating and measurements have been obtained for dozens of NSTX experiments in the last run campaign. Preliminary measurements demonstrate: suppression of edge and core turbulence at the L-H transition; core localized GAE modes, thought to be important to electron transport; a rotational shear dependence of turbulence; and pedestal-localized modes.

February 17, 2011

U.S. Plasma Physicist Honored by the European Physical Society:  The plasma physics division of the European Physical Society (EPS) announced that Professor Patrick H. Diamond of the University of California, San Diego will share the 2011 Hannes Alfvén Prize with Professors Akira Hasegawa and Kunioki Mima, both of Osaka University in Japan. The prestigious Hannes Alfvén Prize—established in 2000 and bearing the name of the only Nobel Prize winner for work in plasma physics—is awarded each year to one or more persons that have made outstanding contributions to plasma physics. The award to Professor Diamond and to the other two scientists is made “for laying the foundations of modern numerical transport simulations and key contributions on self-generated zonal flows and flow shear decorrelation mechanisms which form the basis of modern turbulence in plasmas”. Professor Diamond will receive the award during the opening session of the 38th EPS Conference on Plasma Physics, to be held from June 27 to July 1, 2011, in Strasbourg, France.

February 10, 2011

Imaging of laser wakefield structures featured in Nature Photonics: Intense laser pulses propagating through plasma generate a wake of charge separation creating structures of very strong potential gradients. Accurate visualization is critical to improved understanding of these structures and to the function of devices based on them. In earlier measurements, the team led by Michael Downer at the University of Texas at Austin was able to get a snapshot of the refractive index at a single time-delay behind the pump pulse and built up an image of the structure by combining multi-shot data.  However, due to fluctuations from shot to shot, this method is not accurate enough to observe the evolution of the structure. As highlighted in the February, 2011 issue of Nature Photonics and published in Optics Letters, ZhengYan Li and co-workers from the University of Texas at Austin, have demonstrated a novel imaging technique enabling the observation of the longitudinal structure with a single shot [Optics Letters 35, 4087 (2010)]. By probing at two different angles, combining Frquency-Domain Holography (FDH) and Frequency-Domian Streak Camera (FDSC) techniques, the team has been able to capture the picosecond time evolution of the refractive index structures in a single shot. This work is supported by the Office of Fusion Energy Science Basic Plasma Science program and was awarded through the NSF/DOE Partnership in Basic Plasma Science.

February 10, 2011

Plasma rotation studies in Alcator C-Mod:  Because of the beneficial effects of plasma rotation on stability in tokamaks it is important to understand what causes bulk rotation in fusion plasmas.  Rotation without external torque input, referred to as intrinsic rotation, has been observed on multiple tokamak experiments.  Under certain circumstances on the Alcator C-Mod tokamak the direction of intrinsic rotation in the core plasma actually reverses direction.  These rotation reversals have been observed and studied in C-Mod Ohmic plasmas by ramping the electron density. The density at which the reversal occurs increases linearly with plasma current, and is strongly correlated with the density at which the global energy confinement time switches from the linear (so-called Alcator) regime, where the electron channel appears to dominate, to the saturated Ohmic confinement regime.  This evidence of the potential coupling of transport and rotation will assist with developing models to more accurately predict the rotation velocities in tokamak plasmas.

February 2, 2011

ITER Research on DIII-D:  The ITER facility planned by the international fusion community will be the world’s first burning plasma experiment and will provide the critical science answers for the development of fusion as an energy source.  Motivated  by urgent R&D requirements on ITER, the DIII-D National Fusion Facility has run experiments aimed at successfully mitigating and controlling Edge Localized Modes (ELMs), which are edge disruptions in a fusion plasma that could potentially cause serious damage to power exhaust system if unchecked.  There is a high degree of confidence that based on discoveries at DIII-D and elsewhere, mitigation of ELMs will be possible and that they will not present a performance limiting issue during ITER operations.  DIII-D has also worked to assess the magnetic field effects of Test Blanket Modules (TBMs) on the operations a large-scale magnetically confined fusion device, such as ITER.  U.S. leadership in these areas has moved these two issues well towards a positive resolution in a time frame that is very helpful for ITER.

This research was enabled through a combination of base funding and ARRA support.

June 8-9, 2010

Presentation by M. J. Schaffer for the International TBM Team and the DIII-D Team

Presentation by Ted Strait for the ITER Physics Group

Effective June 7, 2009, Dr. Edmund Synakowski will be the new Associate Director of the Office of Science for the Office of Fusion Energy Sciences (FES) in the U.S. Department of Energy. <more>

May 2009