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Explore bidirectional outflow jets, electron diffusion regions, ion spectroscopy, and 3D magnetic lines in the SSX Laboratory's reconnection experiment supported by US DOE and NSF funding. Discover new simulation results and measurements with high-resolution ion Doppler spectroscopy. Understand the dynamics encoded in lineshape and observations of bi-directional outflows on the Sun. Investigate hot ions and electrons in the SSX device, along with plasma gun setups and ion temperature measurements. Get insights into ion temperature scaling and anomalous signals in this cutting-edge research.
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Bidirectional outflow jets in the SSX reconnection experiment Michael Brown Swarthmore College, NSF Center for Magnetic Self-Organization Chris Cothran, Tim Gray, David Cohen, Vernon Chaplin ’07, Lake Bookman `08, Anna Phillips `10 M. J. Schaffer E. V. Belova Research supported by US DOE and NSF
The SSX Laboratory 10kV/100kA Pulsed power Cylindrical flux conservers and vacuum chamber (=0.40m, L=0.65m) Coaxial magnetized plasma guns on each end (1 mWb)
Tangled 3D magnetic lines (lab and solar) 5 earth diameters tall one foot tall
Reconnection geometry (2D model) Separatrix Current flow (out) Electron flow (in) Inflow (slow) Electron Diffusion Region Outflow (fast, Alfvenic)
3D hybrid simulation (Y. Lin) Kinetic ions (5x108 ions), fluid electrons
Local 3D probe measurements Right-handed Spheromak Left-handed spheromak Reconnected poloidal flux
SSX device (distributed probe array) • Opposing magnetized plasma guns • Close fitting copper flux conserver • Midplane IDS access for flow studies
Outflow jets in SSX • Ion Doppler spectroscopy (jets, heating) • Electron heating (soft x-rays, vacuum ultraviolet) • New results (gas doping and oblate structure)
Bi-directional outflows in SSX High resolution ion Doppler spectroscopy (Cothran, et al, PRL to be submitted J. Fung thesis ‘06)
Observation of bi-directional outflow Data is effectively f(v_r)… one pixel is 10 km/s
Stills from IDS movie Dynamics of the flow (bursts, turbulence) encoded in the lineshape
Bi-directional outflows on the sun D. Innes (SOHO SUMER chromosphere) Innes, Nature, 1997 Innes, Solar Physics, 1997
Location of SUMER slit on solar disk SiIV light dispersed along slit
Velocity resolution 10 km/s Spatial resolution 1000 km Spatially localized events
Hot ions in SSX Cothran, et al (SSX) (low density discharges, after glow discharge conditioning, short gas delay)
Scaling of Ti with density (single sph) Dipole-trapped, Gaussian fit, early in formation (30-40 ms)
Scan of ion mass (moderate density discharges 5 x 1014 cm-3, Different sources for impurity ions) Inconclusive results so far… THe and TSi appear hotter than TC… we are planning careful experiments for summer 2008
IDS ion temperature measurement CIII 229.687 nm (electrodes)
IDS ion temperature measurement HeII 468.57 nm (1% backfill)
IDS ion temperature measurement SiII 462.172 nm (quartz probes)
Hot ions in the extended corona Cranmer, Space Science Rev, 2002 (UVCS)
Hot electrons in SSX Vernon Chaplin ’06 and David Cohen (VUV spectrometer and soft x-ray array)
Typical calculated spectra 12 eV case 28 eV case
Sample SXR signals Anomalously strong signal in high energy bins… electron tail?