CER News:
CER student Tammy Ma wins best talk award at the 2008 UCSD All-Grad Symposium

9 January 2008

Tammy Ma, a PhD student in Professor Farhat Beg's Fast Ignition and Laser-Plasma Interactions group, won the best talk award at the 2008 UCSD All-Grad Symposium in the Physical and Engineering Sciences Panel for her talk entitled "Extreme Ultraviolet Imaging of Petawatt Laser-Irradiated Targets." Her abstract is reproduced below. For more information, contact Tammy at tyma@ucsd.edu

ABSTRACT

Fast ignition is an approach to inertial confinement fusion in which a fusion target is compressed and then heated by a specific series of high intensity laser pulses. In the development of this scheme, among the many issues necessary to explore are the transport of electrons and the flow of energy into a solid target or dense plasma upon irradiation by an ultra-intense laser.

Various targets (planar foils, cones, wires, hemispheres) were shot with the Titan Laser (4x10¹⁹ Wcm^-2) at the Lawrence Livermore National Laboratory. This interaction of a petawatt-laser with a solid target creates a large flux of energetic electrons that heat the material, resulting in a Planckian emission spectrum extending into the extreme ultraviolet (XUV). By recording this radiation, we can obtain excellent images of the interaction region, the energy deposition, and plasma characteristics, as well as measure the surface temperature.

In this talk, I give a brief overview of fast ignition and the use of the XUV diagnostic as both an imaging tool and to determine target temperatures. Experimental results showing evidence of preferential energy transport, electron beam filamentation, and plasma expansion will be presented.