Cross-correlation of spectroscopic and photometric galaxy surveys: cosmology from lensing and redshift distortions

摘要: Cosmological galaxy surveys aim at mapping the largest volumes to test models with techniques such as cluster abundance, cosmic shear correlations or baryon acoustic oscillations (BAO), which are designed be independent of bias. Here we explore an alternative route constrain cosmology: sampling more moderate cross-correlation photometric and spectroscopic surveys. We consider angular galaxy-galaxy autocorrelation in narrow redshift bins its combination dierent probes weak gravitational lensing (WL) space distortions (RSD). Including these improves by factors a few constraints on both dark energy equation state w(z) growth history, parametrized . The additional information comes from using many measurement bias WL RSD, breaking degeneracies that present when each method separately. show forecasts for joint gure merit (FoM w ) linear scales over deep (iAB < 24) survey brighter 22:5) very accurate (0:3%) survey. Magnication sample produce FoMw same order magnitude those RSD BAO sample. However, area yields is up factor 100 times larger. alone, without shape measurements, can also used cross-correlations better results than alone. For follow-up strategy, measuring spectra foreground lenses perform this crosscorrelation provides 5 targeting higher tail distribution study 2.5 larger volume.