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Studying the decay phase of the time intensity profile

Studying the decay phase of the time intensity profile. Feb 24th, 2009 Gang Li. Still can not access the ftp site. From Sollitt's thesis: The decay phase is approximately an exponential decay 1) pure diffusion case, Burlaga, 1967;

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Studying the decay phase of the time intensity profile

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  1. Studying the decay phase of the time intensity profile Feb 24th, 2009 Gang Li Still can not access the ftp site.

  2. From Sollitt's thesis: The decay phase is approximately an exponential decay 1) pure diffusion case, Burlaga, 1967; 2) spatial transport equation, no Duu, (Forman 1971) k = k0 r 3) spatial transport equation, no Duu (Lupton & Stone 1973) k = const.

  3. Connection with Duu I(k)~ k^(-q) Kappa ~ v (RL) ^(2-q) So, if tau ~ 1/ kappa, then tau ~ (A/Q)^(q-2)/v Glenn's beta * (A/Q)^0.4 clustering => q = 1.6 To verify such a clustering, try three different q values: q = 1.35, q=1.6, q=1.8 Note the range of q is NOT large 1<q<2.

  4. To specify the interplanetary turbulence, we use the following two Parameters: As we change q, we assume lc and deltaB^2, the two input parameters from observations DO NOT change. (alternatively, we can require lc change such that the mfp in different q cases give similar values ---- that is a little bit too arbitrary and I am doing it here.

  5. Results: q = 1.6, (2-q) = 0.4 beta*(A/Q)^0.4

  6. Results: q = 1.8, (2-q) = 0.2 beta*(A/Q)^0.2

  7. Results: q = 1.35, (2-q) = 0.65 beta*(A/Q)^0.65

  8. Remarks: The mfps at 1 AU for Helium (3 energies, from small to large) are (in AU): 0.31, 0.38, 0.61 for q = 1.6 0.09, 0.123,0.263 for q = 1.35 1.26, 1.39, 1.74 for q = 1.8 Clearly when mfp is small, we should remove the peak first to find the correct exponential decay phase. This large difference in mfp should NOT be treated too seriously. This is because in reality, people change lc (see page 1-3), which is not a very accurate observable, to get values of mfp that are more or less independent of q. Files: plot_Fe_Q135.qpc, plot_Fe_Q16.qpc, plot_Fe_Q18.qpc are plots for Iron at q=1.35, 1.6 and 1.8. Replace Fe by Helium, Oxygen and proton for other species.

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