Constrained realizations of 2MRS density and peculiar velocity fields: growth rate and local flow

Understand

We generate constrained realizations (CRs) of the density and peculiar velocity fields within $200 \; h^{-1} \, \mathrm{Mpc}$ from the final release of the Two-Micron All-Sky Redshift Survey (2MRS) $-$ the densest all-sky redshift survey to date.

• The CRs are generated by combining a Wiener filter estimator in spherical Fourier-Bessel space with random realizations of log-normally distributed density fields and Poisson-sampled galaxy positions.
• The algorithm is tested and calibrated on a set of semi-analytic mock catalogs mimicking the environment of the Local Group (LG), to rigorously account for the statistical and systematic errors of the reconstruction method.
• By comparing our peculiar velocity CRs with the observed velocities from the Cosmicflows-3 catalog, we constrain the normalized linear growth rate to $f \sigma_8^\mathrm{lin} = 0.367 \pm 0.060$, which is consistent at the $1.1 \sigma$ level with the latest Planck results as well as other direct probes.