nIFTy cosmology: comparison of galaxy formation models

摘要: We present a comparison of 14 galaxy formation models: 12 different semi-analytical models and 2 halo occupation distribution for based upon the same cosmological simulation merger tree information derived from it. The participating codes have proven to be very successful in their own right but they all been calibrated independently using various observational data sets, stellar models, trees. In this paper, we apply them without recalibration leads wide variety predictions mass function, specific star rates, stellar-to-halo ratios, abundance orphan galaxies. scatter is much larger than seen previous studies primarily because used outside native environment within which are well tested calibrated. purpose ‘nIFTy models’ bring together as many modellers possible investigate common approach model calibration. This paper provides unified description presents initial, uncalibrated baseline our future where will develop calibration framework address extent that reduces here.