Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: An Empirical Determination of the Intergalactic Background Light Using
  NIR Deep Galaxy Survey Data out to 5 microns and the Gamma-ray Opacity of the
  Universe   We extend our previous model-independent determination of the intergalactic
background light (IBL), based purely on galaxy survey data, out to a wavelength
of 5 microns. Our approach enables us to constrain the range of photon
densities, based on the uncertainties from observationally determined
luminosity densities and colors. We further determine a 68% confidence upper
and lower limit on the opacity of the universe to gamma-rays up to energies of
1.6/(1+z) TeV. A comparison of our lower limit redshift-dependent opacity
curves to the opacity limits derived from the results of both ground-based air
Cherenkov telescope and Fermi-LAT observations of PKS 1424+240 allows us to
place a new upper limit on the redshift of this source, independent of IBL
modeling.

21
The categories of this paper are: adap-org
25
The categories of this paper are: patt-sol
4
The categories of this paper are: cond-mat
32
The categories of this paper are: atom-ph
14
The categories of this paper are: math-ph
26
The categories of this paper are: bayes-an
2
The categories of this paper are: math
5
The categories of this paper are: gr-qc
30
The categories of this paper are: q-alg
20
The categories of this paper are: acc-phys
22
The categories of this paper are: chao-dyn
15
The categories of this paper are: nucl-ex
9
The categories of this paper are: nlin
31
The categories of this paper are: ao-sci
16
The categories of this paper are: stat
7
The categories of this paper are: hep-th