Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: HI as a Probe of the Large Scale Structure in the Post-Reionization
  Universe   We model the distribution of neutral Hydrogen (HI hereafter) in the
post-reionization universe. This model uses gravity only N-Body simulations and
an ansatz to assign HI to dark matter haloes that is consistent with
observational constraints and theoretical models. We resolve the smallest
haloes that are likely to host HI in the simulations, care is also taken to
ensure that any errors due to the finite size of the simulation box are small.
We then compute the smoothed one point probability distribution function and
the power spectrum of fluctuations in HI. This is compared with other
predictions that have been made using different techniques. We highlight the
significantly high bias for the HI distribution at small scales. This aspect
has not been discussed before. We then discuss the prospects for detection with
the MWA, GMRT and the hypothetical MWA5000. The MWA5000 can detect visibility
correlations at large angular scales at all redshifts in the post-reionization
era. The GMRT can detect visibility correlations at lower redshifts,
specifically there is a strong case for a survey at z=1.3. We also discuss
prospects for direct detection of rare peaks in the HI distribution using the
GMRT. We show that direct detection should be possible with an integration time
that is comparable to, or even less than, the time required for a statistical
detection. Specifically, it is possible to make a statistical detection of the
HI distribution by measuring the visibility correlation, and, direct detection
of rare peaks in the HI distribution at z = 1.3 with the GMRT in less than 1000
hours of observations.

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The categories of this paper are: acc-phys
33
The categories of this paper are: plasm-ph
21
The categories of this paper are: adap-org
34
The categories of this paper are: chem-ph
9
The categories of this paper are: nlin
16
The categories of this paper are: stat
13
The categories of this paper are: quant-ph
29
The categories of this paper are: funct-an
19
The categories of this paper are: eess
4
The categories of this paper are: cond-mat
25
The categories of this paper are: patt-sol
37
The categories of this paper are: supr-con
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The categories of this paper are: hep-lat
18
The categories of this paper are: econ
26
The categories of this paper are: bayes-an
14
The categories of this paper are: math-ph