Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The Discrepancy in Modelling of Galactic Cosmic Ray Primaries and
  Secondaries   Given that the bulk of the galactic cosmic rays (CRs) originates from
transient point-like sources, such as supernova remnants, the flux of the CR
primary component measured at Earth depends on the local source history.
Whereas the secondary omponent shows little to no variation due to nearby
sources, and instead, should depend on the global distribution of CRs.
Steady-state, rotational symmetric models (2D) of CR propagation assume
smeared-out CR sources in the Galaxy and cannot properly take into account the
influence of nearby point sources. In this paper, we infer evidence of nearby
sources by illustrating that a 2D propagation model will not describe CR
primaries and secondaries equally well. We adapted the 2D version of the
GALPROP code to a compute-cluster environment and perform parameter studies
comparing CR spectra with primary and secondary CR data separately. Doing a
parameter study, one may expect different best fit values looking at the
primary and secondary CR components separately, as it is unlikely that the
source history mimicked by the 2D models coincides with the real local source
history. We find that the primaries and secondaries are fitted with differing
best fit parameters, with the results indicating that the 2D model being more
suited to modelling secondary CRs. The insufficient modelling of primary CRs
can be contributed to the possible presence of local CR sources.

16
The categories of this paper are: stat
3
The categories of this paper are: physics
10
The categories of this paper are: q-bio
17
The categories of this paper are: q-fin
25
The categories of this paper are: patt-sol
11
The categories of this paper are: hep-lat
4
The categories of this paper are: cond-mat
0
The categories of this paper are: hep-ph
36
The categories of this paper are: cmp-lg
2
The categories of this paper are: math
35
The categories of this paper are: mtrl-th
14
The categories of this paper are: math-ph
5
The categories of this paper are: gr-qc
27
The categories of this paper are: comp-gas
23
The categories of this paper are: solv-int
26
The categories of this paper are: bayes-an