Observational biases in Lagrangian reconstructions of cosmic velocity fields

Understand

Lagrangian reconstruction of large-scale peculiar velocity fields can be strongly affected by observational biases.

• We develop a thorough analysis of these systematic effects by relying on specially selected mock catalogues.
• For the purpose of this paper, we use the MAK reconstruction method, although any other Lagrangian reconstruction method should be sensitive to the same problems.
• We extensively study the uncertainty in the mass-to-light assignment due to luminosity incompleteness, and the poorly-determined relation between mass and luminosity.