2MTF – IV. A bulk flow measurement of the local Universe Academic Article uri icon


  • © 2014 The Authors. Using the 2MASS near-infrared photometry and high-signal-to-noise HI 21-cm data from the Arecibo, Green Bank, Nancay, and Parkes telescopes, we calculate the redshift-independent distances and peculiar velocities of 2018 bright inclined spiral galaxies over the whole sky. This project is part of the 2MASS Tully-Fisher survey (2MTF), aiming to map the galaxy peculiar velocity field within 100 h-1 Mpc, with an all-sky coverage apart from Galactic latitudes |b|<5°. A x2 minimization method was adopted to analyse the Tully-Fisher peculiarvelocity field in J, H, and K bands, using a Gaussian filter. We combine information from the three wavebands, to provide bulk flow measurements of 310.9 ± 33.9 , 280.8 ± 25.0, and 292.3 ± 27.8 km s-1 at depths of 20, 30, and 40 h-1 Mpc, respectively. Each of these bulk flow vectors points in a direction similar to those found by previous measurements. At each of the three depths, the bulk flow magnitude is consistent with predictions made by the Λ cold dark matter (ΛCDM) model at the 1σ level. The maximum likelihood and minimum variance method were also used to analyse the 2MTF samples, giving similar results.

altmetric score

  • 2.75

author list (cited authors)

  • Hong, T., Springob, C. M., Staveley-Smith, L., Scrimgeour, M. I., Masters, K. L., Macri, L. M., ... Jarrett, T. H.

citation count

  • 29

publication date

  • September 2014