Effect of Strongly Magnetized Electrons and Ions on Heat Flow and Symmetry of Inertial Fusion Implosions
A. Bose, J. Peebles, C. A. Walsh, J. A. Frenje, N. V. Kabadi, P. J. Adrian, G. D. Sutcliffe, M. Gatu Johnson, C. A. Frank, J. R. Davies, R. Betti, V. Yu. Glebov, Fred Marshall, S. P. Regan, C. Stöeckl, E. M. Campbell, H. Sio, J D Moody, Aidan Crilly, Brian Appelbe, J. P. Chittenden, S. Atzeni, F. Barbato, Alessandro Forte, C. K. Li, F. H. Séguin, R. D. Petrasso
Abstract
This Letter presents the first observation on how a strong, 500 kG, externally applied B field increases the mode-two asymmetry in shock-heated inertial fusion implosions. Using a direct-drive implosion with polar illumination and imposed field, we observed that magnetization produces a significant increase in the implosion oblateness (a 2.5× larger P2 amplitude in x-ray self-emission images) compared with reference experiments with identical drive but with no field applied. The implosions produce strongly magnetized electrons (ω_{e}τ_{e}≫1) and ions (ω_{i}τ_{i}>1) that, as shown using simulations, restrict the cross field heat flow necessary for lateral distribution of the laser and shock heating from the implosion pole to the waist, causing the enhanced mode-two shape.