TY - JOUR
T1 - 2MTF - V. Cosmography, β, and the residual bulk flow
AU - Springob, Christopher M.
AU - Hong, Tao
AU - Staveley-Smith, Lister
AU - Masters, Karen L.
AU - Macri, Lucas M.
AU - Koribalski, Barbel S.
AU - Jones, D. Heath
AU - Jarrett, Tom H.
AU - Magoulas, Christina
AU - Erdogdu, Pirin
PY - 2016
Y1 - 2016
N2 - Using the Tully-Fisher relation, we derive peculiar velocities for the 2MASS Tully-Fisher survey and describe the velocity field of the nearby Universe.We use adaptive kernel smoothing to map the velocity field, and compare it to reconstructions based on the redshift space galaxy distributions of the 2MASS Redshift Survey (2MRS) and the IRAS Point Source Catalog Redshift Survey (PSCz). With a standard Χ2 minimization fit to the models, we find that the PSCz model provides a better fit to the 2MTF velocity field data than does the 2MRS model, and provides a value of β in greater agreement with literature values. However, when we subtract away the monopole deviation in the velocity zero-point between data and model, the 2MRS model also produces a value of β in agreement with literature values.We also calculate the 'residual bulk flow': the component of the bulk flow not accounted for by the models. This is ~250 km s-1 when performing the standard fit, but drops to ~150 km s-1 for both models when the aforementioned monopole offset between data and models is removed. This smaller number is more in line with theoretical expectations, and suggests that the models largely account for the major structures in the nearby Universe responsible for the bulk velocity.
AB - Using the Tully-Fisher relation, we derive peculiar velocities for the 2MASS Tully-Fisher survey and describe the velocity field of the nearby Universe.We use adaptive kernel smoothing to map the velocity field, and compare it to reconstructions based on the redshift space galaxy distributions of the 2MASS Redshift Survey (2MRS) and the IRAS Point Source Catalog Redshift Survey (PSCz). With a standard Χ2 minimization fit to the models, we find that the PSCz model provides a better fit to the 2MTF velocity field data than does the 2MRS model, and provides a value of β in greater agreement with literature values. However, when we subtract away the monopole deviation in the velocity zero-point between data and model, the 2MRS model also produces a value of β in agreement with literature values.We also calculate the 'residual bulk flow': the component of the bulk flow not accounted for by the models. This is ~250 km s-1 when performing the standard fit, but drops to ~150 km s-1 for both models when the aforementioned monopole offset between data and models is removed. This smaller number is more in line with theoretical expectations, and suggests that the models largely account for the major structures in the nearby Universe responsible for the bulk velocity.
UR - https://hdl.handle.net/1959.7/uws:63932
U2 - 10.1093/mnras/stv2648
DO - 10.1093/mnras/stv2648
M3 - Article
SN - 0035-8711
VL - 456
SP - 1886
EP - 1900
JO - Monthly Notices of the Royal Astronomical Society
JF - Monthly Notices of the Royal Astronomical Society
IS - 2
ER -