Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The far-infrared--submm spectral energy distribution of high-redshift
  quasars   We combine submm photometric data of z>4 quasars, to obtain a mean
far-infrared (FIR) (rest-frame) spectral energy distribution (SED) of thermal
emission from dust, parameterised by a single temperature (T) and power-law
emissivity index (beta). Best-fit values are T=41+/-5K, beta=1.95+/-0.3. The
redshift spread of this set of quasars is exploited to allow us to sample the
SED at a greater number of rest wavelengths than is possible for a single
object. This parameterisation is of use to any study that extrapolates from a
flux at a single submm wavelength, for example to infer dust masses and FIR
luminosities. We then interpret the submm component as arising from dust heated
by star-formation in the quasar's host galaxy, and investigate a simple scheme
of AGN--host coevolution, in which the timescale for formation of the host
galaxy is c.0.5-1.0Gyr, with star formation proceeding at a constant rate
c.1000Msol/yr. The luminous quasar phase occurs towards the end of the
star-forming period, just before the galaxy's reservoir of cold gas is
depleted. Given the youth of the Universe at z=4 (1.6Gyr), the coexistence of a
massive black hole and a luminous starburst can be a powerful constraint on
models of quasar host-galaxy formation.

22
The categories of this paper are: chao-dyn
14
The categories of this paper are: math-ph
36
The categories of this paper are: cmp-lg
10
The categories of this paper are: q-bio
28
The categories of this paper are: alg-geom
4
The categories of this paper are: cond-mat
24
The categories of this paper are: dg-ga
17
The categories of this paper are: q-fin
31
The categories of this paper are: ao-sci
30
The categories of this paper are: q-alg
37
The categories of this paper are: supr-con
34
The categories of this paper are: chem-ph
27
The categories of this paper are: comp-gas
15
The categories of this paper are: nucl-ex
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The categories of this paper are: solv-int
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The categories of this paper are: funct-an