ISW-LSS CROSS-CORRELATION IN COUPLED DARK ENERGY MODELS WITH MASSIVE NEUTRINOS

We provide an exhaustive analysis of the Integrated Sachs-Wolfe (ISW) effect in the context of coupled dark energy cosmologies where a component of massive neutrinos is also present. We focus on the effects of both the coupling between dark matter and dark energy and of the neutrino mass on the cross-correlation between galaxy/quasar distributions and ISW effect. We provide a simple expression to appropriately rescale the galaxy bias when comparing different cosmologies. Theoretical predictions of the cross-correlation function are then compared with observational data. We find that, while it is not possible to distinguish among the models at low redshifts, discrepancies between coupled models and Lambda CDM increase with z. In spite of this, current data alone does not seem able to distinguish between coupled models and Lambda CDM. However, we show that upcoming galaxy surveys will permit tomographic analysis that will allow us to better discriminate among the models. We discuss the effects on cross-correlation measurements of ignoring galaxy bias evolution, b(z), and magnification bias correction and provide fitting formulae for b(z) for the cosmologies considered. We compare three different tomographic schemes and investigate how the expected signal-to-noise ratio, S/N, of the ISW-LSS cross-correlation changes when increasing the number of tomographic bins. The dependence of S/N on the area of the survey and the survey shot noise is also discussed.