Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Double Extensive Air Shower Induced by Ultra-High Energy Cosmic
  Tau-Neutrino   We investigate the possibility of detecting cosmic ultra-high energy
tau-neutrinos by means of a process involving a double extensive air shower,
the so-called Double-Bang Phenomenon. In this process a primary tau-neutrino
interacts with an atmospheric quark creating a first hadronic shower and a
tau-lepton, which subsequently decays creating a second cascade. The number of
these events strongly depends on the flux of tau-neutrinos arriving at the
Earth's atmosphere and can be used to test some theoretical models related to
the production of ultra-high energy tau-neutrinos. We estimate the potential of
the fluorescence detector of the Pierre Auger Observatory to observe
Double-Bang events. We conclude that for tau-neutrinos with energies ranging
from ~ 0.1 EeV to ~ 10 EeV the number of detected events vary from hundreds in
a year to only few events in hundreds of years.

17
The categories of this paper are: q-fin
31
The categories of this paper are: ao-sci
23
The categories of this paper are: solv-int
34
The categories of this paper are: chem-ph
15
The categories of this paper are: nucl-ex
7
The categories of this paper are: hep-th
27
The categories of this paper are: comp-gas
10
The categories of this paper are: q-bio
1
The categories of this paper are: cs
8
The categories of this paper are: hep-ex
14
The categories of this paper are: math-ph
37
The categories of this paper are: supr-con
9
The categories of this paper are: nlin
33
The categories of this paper are: plasm-ph
30
The categories of this paper are: q-alg
16
The categories of this paper are: stat