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B.V. Jackson Center for Astrophysics and Space Sciences,

The Ability of Radio Heliospheric Remote Sensing Observations to Provide Global Solar Wind Parameters. B.V. Jackson Center for Astrophysics and Space Sciences, University of California at San Diego, LaJolla, CA, USA. ftp://cass185.ucsd.edu/Presentations/2013_jeju. Masayoshi.

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B.V. Jackson Center for Astrophysics and Space Sciences,

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  1. The Ability of Radio Heliospheric Remote Sensing Observations to Provide Global Solar Wind Parameters B.V. Jackson Center for Astrophysics and Space Sciences, University of California at San Diego, LaJolla, CA, USA ftp://cass185.ucsd.edu/Presentations/2013_jeju Masayoshi http://smei.ucsd.edu/ http://ips.ucsd.edu/

  2. More Details IPS (three site- one site)

  3. IPS Radio Systems The Ootacamund (Ooty), India off-axis parabolic cylinder 530 m long and 30 m wide (15,900 m2) operating at a nominal frequency of 326.5 MHz. New STELab IPS array in Toyokawa (3,432 m2 array now operates well – year-round operation began in 2011)

  4. A model of the power spectra of density fluctuations To calculate solar wind velocities using a single IPS station, we use a theoretical power spectrum: an integration of scattering layers along the line of sight (z). The spectrum depends on: λ, ε, v, Θ, α (isotropic medium). Mejia-Ambriz, J., et al., 2013, AGU 2013 Presentation , May, Cancoon, Mexico. Frequency of intensity fluctuations Wave number of solar wind irregularities qx² + qy² =q² Diffractive function (Fresnel function) Visibility function of the source Solar wind velocity Heliocentric distance at the region of IPS (point P) Fresnel knee α ≈ 3.5 ± 0.5 Turbulencespectrumfollows a potentiallaw Fresnel knee Example of the model (log-log): MEXART and STEL observing frequencies.

  5. Comparison between Spectrum Fitting and Cross Correlation Methods from IPS obs. for 3C273 in 2012 3C273 2012/9/3 Correlation ~0.47 V1st/V3st=1.04±0.24 V1st. (km/s) V3st. (km/s) Cross Correlation Method (3-station meas.) Speed V3st.= 457±13 km/s Spectrum Fitting Method (Single-station meas.) Speed V1st.=459km/s Axial Ratio=1.07 Spectral Index=3.8 (Courtesyof M.Tokumaru) Tokumaru, M., et al., 2013, AOGS 2013 Presentation , June, Brisbane, Australia.

  6. 1) Inverse Hessian Method A * xm = b A * xi = -Grad(chiSq) + b xm – xi = A-1 * (-Grad(chiSq) ) 2) Gradient Descent Method dx = C * Grad(chiSq) The Marquardt Method

  7. STEL: 298.000 Single Site: 303.437 Diff: -5.43671 3.1060 2.2460 24.6000 327.0000 0.0001

  8. v0 = 600

  9. V0=344.229

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