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A self consistent model of galaxy formation across cosmic time Bruno Henriques Simon White, Peter Thomas Raul Angulo, Qi Guo, Gerard Lemson, Volker Springel The Munich Model Croton et al. 2006 AGN feedback model (suppression of cooling) De Lucia & Blaizot 2007 dust model SN feedback model - reheating + ejection + reincorporation Guo et al. 2011 different supernova feedback (increased efficiency) Merger treatment Henriques et al. 2011, 2012 different stellar populations Lightcones Henriques B., White S., Lemson G., Thomas P., Guo Q., Marleau D., Overzier R., 2012, MNRAS Extended photometric coverage Multiple Stellar Populations Pencil Beams + All Sky http://www.mpa-garching.mpg.de B-band Luminosity Function Stellar Mass Function K-band Luminosity Function MCMC Parameter Sampling Henriques B., Thomas P., Oliver S., Roseboom I., MNRAS, 2009 Henriques B., Thomas P., MNRAS, 2010 Complex galaxy formation physics Large Volume Semi-analytic modelling MCMC Across Cosmic Time Constrain the model at multiple redshifts Choose observational constraints Stellar Mass Function, K-band & B-band Luminosity Functions Choose parameters to sample Star formation, SN feedback, AGN feedback efficiency, Metals yield Time varying parameters A clear & unique change was revealed by the pre-processing step Reincorporation of gas after ejection by SN feedback ( high-z low-z ) All other parameters have consistent regions at all z Any other parametrisation with time is ruled out, for example, in our model, a change in star formation efficiency is ruled out. New parametrization Reincorporation time scaling with Mvir, due to the slow down of outgoing material caused by dynamical friction. Single Set Strong ejection + no reincorporation set the low mass end at high-z Strong reincorporation at later times produces the required build up for z<1 Results Colors and SFR The delayed reincorporation of gas shifts star formation towards lower redshift. Dwarfs are bluer, have higher star formation rates and younger ages. Clustering Dwarf galaxies form later, in higher mass halos that are less cluster. Galaxy formation physics, and not just cosmology, have a strong impact on galaxy clusterin. Conclusions Extend the MCMC sampling to multiple redshifts for a wide range of observations, taking full advantage of the self-consistent evolution of galaxies Pre-processing step that shows Guo11 parametrization to be nearly optimal at z=0. Reincorporation change required by the evolution of galaxy properties. Simple adjustment to the model allows us to get a reasonable fit at all redshifts for the masses, K-band and B-band luminosities. There is no longer an excess of dwarfs at high redshift Evolution of the massive end is reproduced across cosmic time Extended MCMC Capabilities Observational constraints at multiple redshifts Stellar mass and luminosity functions constraints from z=3 to z=0 Takes full advantage of the self-consistent evolution of galaxies Time-evolution of parameters (pre-processing step) If not needed, the current parametrisation is not ruled out by observations If needed, a different parametrisation is required (it rules out any others) If a good fit can not be found, the current model is ruled out M05 vs BC03 Gas TB-AGB TB-AGB + RHeB