Experiments on the Propagation of Plasma Filaments

@article{citeulike:2963524, abstract = {We investigate experimentally the motion and structure of isolated plasma filaments propagating through neutral gas. Plasma filaments, or \“blobs,\” arise from turbulent fluctuations in a range of plasmas. Our experimental geometry is toroidally symmetric, and the blobs expand to a larger major radius under the influence of a vertical electric field. The electric field, which is caused by B and curvature drifts in a 1/R magnetic field, is limited by collisional damping on the neutral gas. The blob's electrostatic potential structure and the resulting E\×B flow field give rise to a vortex pair and a mushroom shape, which are consistent with nonlinear plasma simulations. We observe experimentally this characteristic mushroom shape for the first time. We also find that the blob propagation velocity is inversely proportional to the neutral density and decreases with time as the blob cools.}, author = {Katz, Noam and Egedal, Jan and Fox, Will and Le, Ari and Porkolab, Miklos }, citeulike-article-id = {2963524}, doi = {10.1103/PhysRevLett.101.015003}, journal = {Physical Review Letters}, keywords = {filament, gas, neutral, plasma, propagation}, number = {1}, posted-at = {2008-07-04 10:51:46}, priority = {2}, publisher = {APS}, title = {Experiments on the Propagation of Plasma Filaments}, url = {http://scitation.aip.org/getabs/servlet/GetabsServlet?prog=normal\&id=PRLTAO000101000001015003000001\&idtype=cvips\&gifs=yes}, volume = {101}, year = {2008} }

TY - JOUR ID - citeulike:2963524 L3 - citeulike-article-id:2963524 TI - Experiments on the Propagation of Plasma Filaments JF - Physical Review Letters VL - 101 IS - 1 PB - APS N2 - We investigate experimentally the motion and structure of isolated plasma filaments propagating through neutral gas. Plasma filaments, or “blobs,” arise from turbulent fluctuations in a range of plasmas. Our experimental geometry is toroidally symmetric, and the blobs expand to a larger major radius under the influence of a vertical electric field. The electric field, which is caused by B and curvature drifts in a 1/R magnetic field, is limited by collisional damping on the neutral gas. The blob's electrostatic potential structure and the resulting E×B flow field give rise to a vortex pair and a mushroom shape, which are consistent with nonlinear plasma simulations. We observe experimentally this characteristic mushroom shape for the first time. We also find that the blob propagation velocity is inversely proportional to the neutral density and decreases with time as the blob cools. KW - filament KW - gas KW - neutral KW - plasma KW - propagation AU - Katz, Noam AU - Egedal, Jan AU - Fox, Will AU - Le, Ari AU - Porkolab, Miklos PY - 2008/// UR - http://scitation.aip.org/getabs/servlet/GetabsServlet?prog=normal&id=PRLTAO000101000001015003000001&idtype=cvips&gifs=yes ER -