Speaker
Dr
Roger Ygbuhay
(University of New Mexico)
Description
At high rigidities (≥ 10 GV) galactic cosmic ray (GCR) particle density gradients and mean free paths (λ) in turbulent interplanetary magnetic field (B) at 1 a.u. can only be computed from the solar diurnal anisotropy (SDA) data. Long-term changes of SDA components recorded by the global network of neutron monitors (NMs) with long track records are used to compute the annual mean values of the heliospheric modulation parameters for 1963-2013 using the concept of galactic cosmic ray isotropic hard sphere scattering in the solar wind plasma. The computations of coefficient α (= λ⊥/ ) at 1 a.u were reported at the 40th COSPAR Scientific Assembly held in Moscow in 2014. In this paper we present the computed values of the product of the cyclotron frequency (ω) and mean time between diffusive collisions (τ) as well as mean free path parallel to mean B ( ), radial density gradient (Gr) and asymmetric density gradient (Gθa) with respect to heliospheric current sheet (HCS) and discuss their dependence on GCR rigidity, positive (p-) and negative (n-) polarity intervals of B and sunspot activity.
| Registration number following "ICRC2015-I/" | 1028 |
|---|---|
| Collaboration | -- not specified -- |
Author
Dr
Roger Ygbuhay
(University of New Mexico)
Co-authors
Prof.
H.S. Ahluwalia
(University of New Mexico)
Prof.
L.I. Dorman
(Tel Aviv University)
Dr
Renata Modzelewska
(Siedlce University)
