Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Measuring cosmic velocities with 21cm intensity mapping and galaxy
  redshift survey cross-correlation dipoles   We investigate the feasibility of measuring the effects of peculiar
velocities in large-scale structure using the dipole of the redshift-space
cross-correlation function. We combine number counts of galaxies with
brightness-temperature fluctuations from 21cm intensity mapping, demonstrating
that the dipole may be measured at modest significance ($\lesssim 2\sigma$) by
combining the upcoming radio survey CHIME with the future redshift surveys of
DESI and Euclid. More significant measurements ($\lesssim~10\sigma$) will be
possible by combining intensity maps from the SKA with these of DESI or Euclid,
and an even higher significance measurement ($\lesssim 100\sigma$) may be made
by combining observables completely internally to the SKA. We account for
effects such as contamination by wide-angle terms, interferometer noise and
beams in the intensity maps, non-linear enhancements to the power spectrum,
stacking multiple populations, sensitivity to the magnification slope, and the
possibility that number counts and intensity maps probe the same tracers. We
also derive a new expression for the covariance matrix of multi-tracer
redshift-space correlation function estimators with arbitrary orientation
weights, which may be useful for upcoming surveys aiming at measuring
redshift-space clustering with multiple tracers.

12
The categories of this paper are: nucl-th
25
The categories of this paper are: patt-sol
8
The categories of this paper are: hep-ex
20
The categories of this paper are: acc-phys
36
The categories of this paper are: cmp-lg
33
The categories of this paper are: plasm-ph
17
The categories of this paper are: q-fin
23
The categories of this paper are: solv-int
14
The categories of this paper are: math-ph
15
The categories of this paper are: nucl-ex
22
The categories of this paper are: chao-dyn
32
The categories of this paper are: atom-ph
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The categories of this paper are: alg-geom
30
The categories of this paper are: q-alg
13
The categories of this paper are: quant-ph
26
The categories of this paper are: bayes-an