Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Understanding the Effect of Atmospheric Density on the Cosmic Ray Flux
  Variations at the Earth Surface   We report in this letter for the first time the numerical simulations of muon
and neutron flux variations at the surface of the earth with varying air
densities in the troposphere and stratosphere. The simulated neutron and muon
flux variations are in very good agreement with the measured neutron flux
variation in Oulu and the muon flux variation in Atlanta. We conclude from this
study that the stratosphere air density variation dominates the effects on the
muon flux changes while the density variation in troposphere mainly influences
the neutron count variation. These results pave a new path for systematically
studying the global temperature evolution using worldwide cosmic ray data.

20
The categories of this paper are: acc-phys
12
The categories of this paper are: nucl-th
15
The categories of this paper are: nucl-ex
34
The categories of this paper are: chem-ph
5
The categories of this paper are: gr-qc
36
The categories of this paper are: cmp-lg
30
The categories of this paper are: q-alg
14
The categories of this paper are: math-ph
4
The categories of this paper are: cond-mat
32
The categories of this paper are: atom-ph
37
The categories of this paper are: supr-con
35
The categories of this paper are: mtrl-th
29
The categories of this paper are: funct-an
22
The categories of this paper are: chao-dyn
19
The categories of this paper are: eess
33
The categories of this paper are: plasm-ph