Weak lensing with 21 cm intensity mapping at z ∼ 2–3

  title={Weak lensing with 21 cm intensity mapping at z ∼ 2–3},
  author={Alkistis Pourtsidou and R. Benton Metcalf},
  journal={Monthly Notices of the Royal Astronomical Society},
ABSTRACT We study how 21 cm intensity mapping can be used to measure gravitational lensingover a wide range of redshift. This can extend weak lensing measurements to higherredshifts than are accessible with conventional galaxy surveys. We construct a con-vergence estimator taking into account the discreteness of galaxies and calculate theexpected noise level as a function of redshift and telescope parameters. At z ˘ 2 3 we nd that a telescope array with a collecting area ˘ 0:2km 2 spread over a… 

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