[1] The solar wind (SW) and interplanetary magnetic field (IMF) have a significant influence on the near-Earth space environment. In this study we evaluate and compare forecasts from two models that predict SW and IMF conditions: the Hakamada-Akasofu-Fry (HAF) version 2, operational at the Air Force Weather Agency, and Wang-Sheeley-Arge (WSA) version 1.6, executed routinely at the Space Weather Prediction Center. SW speed (V sw ) and IMF polarity (B pol ) forecasts at L1 were compared with Wind and Advanced Composition Explorer satellite observations. Verification statistics were computed by study year and forecast day. Results revealed that both models' mean V sw are slower than observed. The HAF slow bias increases with forecast duration. WSA had lower V sw forecastobservation difference (F-O) absolute means and standard deviations than HAF. HAF and WSA V sw forecast standard deviations were less than observed. V sw F-O mean square skill rarely exceeds that of recurrence forecasts. B pol is correctly predicted 65%-85% of the time in both models. Recurrence beats the models in B pol skill in nearly every year forecast day category. Verification by "event" (flare events ≤5 days before forecast start) and "nonevent" (no flares) forecasts showed that most HAF V sw bias growth, F-O standard deviation decrease, and forecast standard deviation decrease were due to the event forecasts. Analysis of single time step V sw increases of ≥20% in the nonevent forecasts indicated that both models predicted too many occurrences and missed many observed incidences. Neither model had skill above a random guess in predicting V sw increase arrival time at L1.

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Devices that form and accelerate field reversed configuration plasma may potentially be applied to spacecraft propulsion. Propulsion applications require heavy-gas plasma and the fundamental processes for heavy-gas field reversed configuration formation are still not well understood. Pre-ionization plasma properties are known to influence the success and final properties of field reversed configuration formation. In the following study the magnetic field of the pre-ionization stage of a heavy-gas field reversed configuration test article is presented. Initial results show discharge frequencies increase in the presence of plasma from 440 kHz in atmosphere discharges with no plasma to 472 kHz in 33 mTorr of air with plasma, both at an initial charge of 15 kV. Calibration of a three-axis magnetic field probe is completed using EMC Studio. Calibration values for the axial and azimuthal components of the probe are 4.66x10 8 and 9.45x10 7 G/V, respectfully. Magnetic field measurements at 15 and 20 kV are presented. The 15 and 20 kV discharges produce a peak current of 38 and 50 kA, respectfully. EMC simulations using these peak current values produce a maximum axial magnetic field of 632 and 819 G, respectfully. Measured axial magnetic field strengths of MPX at 15 and 20 kV using the B-dot probe yield 640 and 885 G, respectfully.

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