Probing Cosmic Acceleration by Using the SNLS3 SNIa Dataset
  We probe the cosmic acceleration by using the recently released SNLS3 sample
of 472 type Ia supernovae. Combining this type Ia supernovae dataset with the
cosmic microwave background anisotropy data from the Wilkinson Microwave
Anisotropy Probe 7-yr observations, the baryon acoustic oscillation results
from the Sloan Digital Sky Survey data release 7, and the Hubble constant
measurement from the Wide Field Camera 3 on the Hubble Space Telescope, we
measure the dark energy equation of state $w$ and the deceleration parameter
$q$ as functions of redshift by using the Chevallier-Polarski-Linder
parametrization. Our result is consistent with a cosmological constant at
1$\sigma$ confidence level, without evidence for the recent slowing down of the
cosmic acceleration. Furthermore, we consider three binned parametrizations
($w$ is piecewise constant in redshift $z$) based on different binning methods.
The similar results are obtained, i.e., the $\Lambda$CDM model is still nicely
compatible with current observations.
