Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The geometry of atmospheric neutrino production   The zenith angle distributions of atmospheric neutrinos are determined by the
possible presence of neutrino oscillations and the combination of three most
important contributions: (1) geomagnetic effects on the primary cosmic rays,
that suppress the primary flux in the Earth's magnetic equatorial region, (2)
the zenith angle dependence of the neutrino yields, due to the fact that
inclined showers produce more neutrinos, and (3) geometrical effects due to the
spherical shell geometry of the neutrino production volume. The last effect has
been recognized only recently and results in an important enhancement of the
flux of sub--GeV neutrinos for horizontal directions. In this work we discuss
the geometrical effect and its relevance in the interpretation of the
atmospheric neutrino data.

16
The categories of this paper are: stat
37
The categories of this paper are: supr-con
34
The categories of this paper are: chem-ph
25
The categories of this paper are: patt-sol
13
The categories of this paper are: quant-ph
19
The categories of this paper are: eess
1
The categories of this paper are: cs
21
The categories of this paper are: adap-org
11
The categories of this paper are: hep-lat
22
The categories of this paper are: chao-dyn
12
The categories of this paper are: nucl-th
18
The categories of this paper are: econ
32
The categories of this paper are: atom-ph
20
The categories of this paper are: acc-phys
31
The categories of this paper are: ao-sci
26
The categories of this paper are: bayes-an