Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: HI Intensity Mapping for Clustering-Based Redshift Estimation   Precision cosmology requires accurate galaxy redshifts, but next generation
optical surveys will observe unprecedented numbers of resolved galaxies,
placing strain on the amount of spectroscopic follow-up required. We show how
useful information can be gained on the redshift distributions of optical
galaxy samples from spatial cross-correlations with intensity maps of
unresolved HI (21cm) spectral line emission. We construct a redshift
distribution estimator, which we test using simulations. We utilise the S3-SAX
catalogue which includes HI emission information for each galaxy, which we use
to construct HI intensity maps. We also make use of simulated LSST and
Euclid-like photometry enabling us to apply the HI clustering calibration to
realistic simulated photometric redshifts. While taking into account important
limitations to HI intensity mapping such as lost k-modes from foreground
cleaning and poor angular resolution due to large receiver beams, we show that
excellent constraints on redshift distributions can be provided for an optical
photometric sample.

11
The categories of this paper are: hep-lat
15
The categories of this paper are: nucl-ex
27
The categories of this paper are: comp-gas
29
The categories of this paper are: funct-an
2
The categories of this paper are: math
28
The categories of this paper are: alg-geom
18
The categories of this paper are: econ
5
The categories of this paper are: gr-qc
10
The categories of this paper are: q-bio
8
The categories of this paper are: hep-ex
13
The categories of this paper are: quant-ph
12
The categories of this paper are: nucl-th
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The categories of this paper are: patt-sol
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The categories of this paper are: nlin
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The categories of this paper are: eess
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The categories of this paper are: q-fin