The galaxy-subhalo connection in low-redshift galaxy clusters from weak gravitational lensing

Understand

We measure the gravitational lensing signal around satellite galaxies in a sample of galaxy clusters at $z<0.15$ by combining high-quality imaging data from the Canada-France-Hawaii Telescope with a large sample of spectroscopically-confirmed cluster members.

• We use extensive image simulations to assess the accuracy of shape measurements of faint, background sources in the vicinity of bright satellite galaxies.
• We find a small but significant bias, as light from the lenses makes the shapes of background galaxies appear radially aligned with the lens.
• We account for this bias by applying a correction that depends on both lens size and magnitude.