Measuring cosmic bulk flows with Type Ia Supernovae from the Nearby
  Supernova Factory
  Context. Our Local Group of galaxies appears to be moving relative to the
cosmic microwave background with the source of the peculiar motion still
uncertain. While in the past this has been studied mostly using galaxies as
distance indicators, the weight of type Ia supernovae (SNe Ia) has increased
recently with the continuously improving statistics of available low-redshift
supernovae.
  Aims. We measured the bulk flow in the nearby universe ($0.015 < z < 0.1$)
using 117 SNe Ia observed by the Nearby Supernova Factory, as well as the
Union2 compilation of SN Ia data already in the literature.
  Methods. The bulk flow velocity was determined from SN data binned in
redshift shells by including a coherent motion (dipole) in a cosmological fit.
Additionally, a method of spatially smoothing the Hubble residuals was used to
verify the results of the dipole fit. To constrain the location and mass of a
potential mass concentration (e.g., the Shapley supercluster) responsible for
the peculiar motion, we fit a Hubble law modified by adding an additional mass
concentration.
  Results. The analysis shows a bulk flow that is consistent with the direction
of the CMB dipole up to $z \sim 0.06$, thereby doubling the volume over which
conventional distance measures are sensitive to a bulk flow. We see no
significant turnover behind the center of the Shapley supercluster. A simple
attractor model in the proximity of the Shapley supercluster is only marginally
consistent with our data, suggesting the need for another, more distant source.
In the redshift shell $0.06 < z < 0.1$, we constrain the bulk flow velocity to
$< 240~\textrm{km s}^{-1}$ (68% confidence level) for the direction of the CMB
dipole, in contradiction to recent claims of the existence of a large-amplitude
dark flow.
