Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Neutrino, Photon Interaction in Unparticle Physics   We investigate the impact of unparticle physics on the annihilation of relic
neutrinos with the neutrinos identified as primary source of ultra high energy
(UHE) cosmic ray events, producing a cascade of photons and charged particles.
We compute the contribution of the unparticle exchange to the cross-sections
$\nu \bar\nu\to\gamma \gamma$ and $\nu \bar\nu\to f \bar f$ scattering. We
estimate the neutrino photon decoupling temperature from the reaction rate of
$\nu \bar\nu\to\gamma \gamma$. We find that inclusion of unparticles can in
fact account for the flux of UHE cosmic rays and can also result in the
lowering of neutrino - photon decoupling temperature below the QCD phase
transition for unparticle physics parameters in a certain range. We calculate
the mean free path of these high energy neutrinos annihilating themselves with
the relic neutrinos to produce vector and tensor unparticles.

20
The categories of this paper are: acc-phys
36
The categories of this paper are: cmp-lg
31
The categories of this paper are: ao-sci
15
The categories of this paper are: nucl-ex
7
The categories of this paper are: hep-th
12
The categories of this paper are: nucl-th
29
The categories of this paper are: funct-an
19
The categories of this paper are: eess
2
The categories of this paper are: math
1
The categories of this paper are: cs
4
The categories of this paper are: cond-mat
18
The categories of this paper are: econ
30
The categories of this paper are: q-alg
21
The categories of this paper are: adap-org
22
The categories of this paper are: chao-dyn
25
The categories of this paper are: patt-sol