Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Trinity: An Imaging Air Cherenkov Telescope to Search for
  Ultra-High-Energy Neutrinos   Earth-skimming neutrinos are those which travel through the Earth's crust at
a shallow angle. For Ultra-High-Energy (E > 1 PeV; UHE) earth-skimming tau
neutrinos, there is a high-probability that the tau lepton created by a
neutrino-Earth interaction will emerge from the ground before it decays. When
this happens, the decaying tau particle initiates an air shower of relativistic
sub-atomic particles which emit Cherenkov radiation. To observe this Cherenkov
radiation, we propose the Trinity Observatory. Using a novel optical structure
design, pointing at the horizon, Trinity will observe the Cherenkov radiation
from upward-going neutrino-induced air showers. Being sensitive to neutrinos in
the 1-10,000 PeV energy range, Trinity's expected sensitivity will have a
unique role to play filling the gap between the observed astrophysical
neutrinos observed by IceCube and the expected sensitivity of radio UHE
neutrino detectors.

25
The categories of this paper are: patt-sol
3
The categories of this paper are: physics
19
The categories of this paper are: eess
15
The categories of this paper are: nucl-ex
9
The categories of this paper are: nlin
29
The categories of this paper are: funct-an
28
The categories of this paper are: alg-geom
23
The categories of this paper are: solv-int
24
The categories of this paper are: dg-ga
31
The categories of this paper are: ao-sci
4
The categories of this paper are: cond-mat
20
The categories of this paper are: acc-phys
37
The categories of this paper are: supr-con
36
The categories of this paper are: cmp-lg
35
The categories of this paper are: mtrl-th
10
The categories of this paper are: q-bio