Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Modelling intergalactic low ionisation metal absorption line systems
  near the epoch of reionization   We interpret observations of intergalactic low ionisation metal absorption
systems at redshifts z $\gtrsim$5 in terms of pressure-confined clouds. We find
clouds confined by the expected pressure of galactic haloes with masses
$11<\log M_h/h^{-1}M_\odot<12$ provide a good description of the column density
ratios between low ionisation metal absorbers. Some of the ratios, however,
require extending conventional radiative transfer models of irradiated slabs to
spherical (or cylindrical) clouds to allow for lines of sight passing outside
the cores of the clouds. Moderate depletion of silicon onto dust grains is also
indicated in some systems. The chemical abundances inferred span the range
between solar and massive-star dominated stellar populations as may arise in
starburst galaxies. The typical HI column densities matching the data
correspond to Damped Lyman-$\alpha$ Absorbers (DLAs) or sub-DLAs, with sizes of
40 pc to 3 kpc, gas masses $3.5<\log M_c/M_\odot<8$ and metallicites
$0.001-0.01Z_\odot$. Such systems continue to pose a challenge for galaxy-scale
numerical simulations to reproduce.

24
The categories of this paper are: dg-ga
2
The categories of this paper are: math
10
The categories of this paper are: q-bio
18
The categories of this paper are: econ
27
The categories of this paper are: comp-gas
13
The categories of this paper are: quant-ph
33
The categories of this paper are: plasm-ph
35
The categories of this paper are: mtrl-th
5
The categories of this paper are: gr-qc
23
The categories of this paper are: solv-int
1
The categories of this paper are: cs
17
The categories of this paper are: q-fin
8
The categories of this paper are: hep-ex
30
The categories of this paper are: q-alg
4
The categories of this paper are: cond-mat
15
The categories of this paper are: nucl-ex