Approximation of the potential in scalar field dark energy models
  We study the nature of potentials in scalar field based models for dark
energy - with both canonical and noncanonical kinetic terms. We calculate
numerically, and using an analytic approximation around $a\approx 1$,
potentials for models with constant equation-of-state parameter, $w_{\phi}$. We
find that for a wide range of models with canonical and noncanonical kinetic
terms there is a simple approximation for the potential that holds when the
scale factor is in the range $0.6\lesssim a\lesssim 1.4$. We discuss how this
form of the potential can also be used to represent models with non-constant
$w_{\phi}$ and, hence, how it could be used in reconstruction from cosmological
data.
