Dark energy constraints from a space-based supernova survey
  We present a forecast of dark energy constraints that could be obtained from
a large sample of distances to Type Ia supernovae detected and measured from
space. We simulate the supernova events as they would be observed by a
EUCLID-like telescope with its two imagers, assuming those would be equipped
with 4 visible and 3 near infrared swappable filters. We account for known
systematic uncertainties affecting the cosmological constraints, including
those arising through the training of the supernova model used to fit the
supernovae light curves. Using conservative assumptions and Planck priors, we
find that a 18 month survey would yield constraints on the dark energy equation
of state comparable to the cosmic shear approach in EUCLID: a variable
two-parameter equation of state can be constrained to ~0.03 at z~0.3. These
constraints are derived from distances to about 13,000 supernovae out to z=1.5,
observed in two cones of 10 and 50 deg^2. These constraints do not require
measuring a nearby supernova sample from the ground. Provided swappable filters
can be accommodated on EUCLID, distances to supernovae can be measured from
space and contribute to obtain the most precise constraints on dark energy
properties.
