Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Energy Feedback from X-ray Binaries in the Early Universe   X-ray photons, because of their long mean-free paths, can easily escape the
galactic environments where they are produced, and interact at long distances
with the inter-galactic medium, potentially having a significant contribution
to the heating and reionization of the early Universe. The two most important
sources of X-ray photons in the Universe are active galactic nuclei (AGN) and
X-ray binaries (XRBs). In this Letter we use results from detailed, large scale
population synthesis simulations to study the energy feedback of XRBs, from the
first galaxies (z~ 20) until today. We estimate that X-ray emission from XRBs
dominates over AGN at z>6-8. The shape of the spectral energy distribution of
the emission from XRBs shows little change with redshift, in contrast to its
normalization which evolves by ~4 orders of magnitude, primarily due to the
evolution of the cosmic star-formation rate. However, the metallicity and the
mean stellar age of a given XRB population affect significantly its X-ray
output. Specifically, the X-ray luminosity from high-mass XRBs per unit of
star-formation rate varies an order of magnitude going from solar metallicity
to less than 10% solar, and the X-ray luminosity from low-mass XRBs per unit of
stellar mass peaks at an age of ~300 Myr and then decreases gradually at later
times, showing little variation for mean stellar ages > 3 Gyr. Finally, we
provide analytical and tabulated prescriptions for the energy output of XRBs,
that can be directly incorporated in cosmological simulations.

23
The categories of this paper are: solv-int
2
The categories of this paper are: math
37
The categories of this paper are: supr-con
13
The categories of this paper are: quant-ph
9
The categories of this paper are: nlin
33
The categories of this paper are: plasm-ph
32
The categories of this paper are: atom-ph
8
The categories of this paper are: hep-ex
36
The categories of this paper are: cmp-lg
30
The categories of this paper are: q-alg
25
The categories of this paper are: patt-sol
0
The categories of this paper are: hep-ph
20
The categories of this paper are: acc-phys
27
The categories of this paper are: comp-gas
12
The categories of this paper are: nucl-th
26
The categories of this paper are: bayes-an