Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Interplanetary spread of solar energetic protons near a high-speed solar
  wind stream   We study how a high-speed solar wind stream embedded in a slow solar wind
influences the spread of solar energetic protons in interplanetary space. To
model the energetic protons, we used a recently developed particle transport
code that computes particle distributions in the heliosphere by solving the
focused transport equation in a stochastic manner. The particles are propagated
in a solar wind containing a CIR, which was generated by the heliospheric
magnetohydrodynamic model, EUHFORIA. We study four cases in which we assume a
delta injection of 4 MeV protons spread uniformly over different regions at the
inner boundary of the model. These source regions have the same size and shape,
yet are shifted in longitude from each other, and are therefore magnetically
connected to different solar wind conditions. The intensity and anisotropy
profiles along selected IMF lines vary strongly according to the different
solar wind conditions encountered along the field line. The IMF lines crossing
the shocks bounding the CIR show the formation of accelerated particle
populations, with the reverse shock wave being a more efficient accelerator
than the forward shock wave. Moreover, we demonstrate that the longitudinal
width of the particle intensity distribution can increase, decrease, or remain
constant with heliographic radial distance, reflecting the underlying IMF
structure. Finally, we show how the deflection of the IMF at the shock waves
and the compression of the IMF in the CIR deforms the three-dimensional shape
of the particle distribution in such a way that the original shape of the
injection profile is lost.

28
The categories of this paper are: alg-geom
8
The categories of this paper are: hep-ex
20
The categories of this paper are: acc-phys
11
The categories of this paper are: hep-lat
5
The categories of this paper are: gr-qc
33
The categories of this paper are: plasm-ph
14
The categories of this paper are: math-ph
9
The categories of this paper are: nlin
2
The categories of this paper are: math
19
The categories of this paper are: eess
1
The categories of this paper are: cs
22
The categories of this paper are: chao-dyn
12
The categories of this paper are: nucl-th
27
The categories of this paper are: comp-gas
25
The categories of this paper are: patt-sol
36
The categories of this paper are: cmp-lg