Supernovae with 'super-Hipparcos'

GAIA is the 'super-Hipparcos ' satellite scheduled for launch in 2010 by the European Space Agency. It is a scanning satellite that carries out multi-colour, multi-epoch photometry on all objects brighter than 20th mag. We conduct detailed simulations of supernovae (SNe) detection by GAIA . Supernovae of each type are chosen according to the observed distributions of absolute magnitudes, and located in nearby galaxies according to the local large-scale structure. Using an extinction model of the Galaxy and the scanning law of the GAIA satellite, we calculate how many SNe are detectable as a function of the phase of the light curve. Our study shows that GAIA will report data on similar to21 400 SNe during the five-year mission lifetime, of which similar to14 300 are SNe Ia, similar to1400 are SNe Ib/c and similar to5700 are SNe II. Using the simulations, we estimate that the numbers caught before maximum are similar to6300 SNe Ia, similar to500 SNe Ib/c and similar to1700 SNe II. During the mission lifetime, GAIA will issue about 5 SNe alerts a day. The most distant SNe accessible to GAIA are at a redshift z similar to 0.14 and so GAIA will provide a huge sample of local SNe. There will be many examples of the rarer subluminous events, over-luminous events, SNe Ib/c and SNe II-L. SNe rates will be found as a function of galaxy type, as well as extinction and position in the host galaxy. Amongst other applications, there may be about 26 SNe each year for which detection of gravitational waves is possible and about 180 SNe each year for which detection of gamma-rays is possible. GAIA 's astrometry will provide the SN position to better than milliarcseconds, offering opportunities for the identification of progenitors in nearby galaxies and for studying the spatial distribution of SNe of different types in galaxies.