%0 Generic %1 vandaalen2013impact %A van Daalen, Marcel P. %A Schaye, Joop %A McCarthy, Ian G. %A Booth, C. M. %A Vecchia, Claudio Dalla %D 2013 %K baryon correlation function galaxy %T The impact of baryonic processes on the two-point correlation functions of galaxies, subhaloes and matter %U http://arxiv.org/abs/1310.7571 %X The observed clustering of galaxies and the cross-correlation of galaxies and mass (a measure of galaxy-galaxy lensing) provide important constraints on both cosmology and models of galaxy formation. Even though the dissipation, and more importantly the feedback processes associated with galaxy formation are thought to affect the distribution of matter, essentially all models used to predict clustering data are based on dark matter only simulations. Here, we use large hydrodynamical simulations to investigate how galaxy formation affects the autocorrelation functions of galaxies, subhaloes, as well as their cross-correlation with matter. We show that the changes due to the inclusion of baryons are not limited to small scales and are even present in samples selected by subhalo mass. Samples selected by subhalo mass cluster ~10% more strongly in a baryonic run on scales r ~ 1Mpc/h or larger, and this difference increases for smaller separations. While the inclusion of baryons boosts the clustering at fixed subhalo mass on all scales, the sign of the effect on the cross-correlation of subhaloes with matter can vary with radius. By linking subhaloes between simulations, we show that the large-scale effects are due to the change in subhalo mass caused by the strong feedback associated with galaxy formation and may therefore not affect samples selected by number density. However, on scales r < r_vir significant differences remain after accounting for the change in subhalo mass. We conclude that predictions for galaxy-galaxy and galaxy-mass clustering from models based on dark matter only simulations will have errors greater than 10% on sub-Mpc scales, unless the simulation results are modified to correctly account for the effects of baryons on the distributions of mass and satellites.

@misc{vandaalen2013impact, abstract = {The observed clustering of galaxies and the cross-correlation of galaxies and mass (a measure of galaxy-galaxy lensing) provide important constraints on both cosmology and models of galaxy formation. Even though the dissipation, and more importantly the feedback processes associated with galaxy formation are thought to affect the distribution of matter, essentially all models used to predict clustering data are based on dark matter only simulations. Here, we use large hydrodynamical simulations to investigate how galaxy formation affects the autocorrelation functions of galaxies, subhaloes, as well as their cross-correlation with matter. We show that the changes due to the inclusion of baryons are not limited to small scales and are even present in samples selected by subhalo mass. Samples selected by subhalo mass cluster ~10% more strongly in a baryonic run on scales r ~ 1Mpc/h or larger, and this difference increases for smaller separations. While the inclusion of baryons boosts the clustering at fixed subhalo mass on all scales, the sign of the effect on the cross-correlation of subhaloes with matter can vary with radius. By linking subhaloes between simulations, we show that the large-scale effects are due to the change in subhalo mass caused by the strong feedback associated with galaxy formation and may therefore not affect samples selected by number density. However, on scales r < r_vir significant differences remain after accounting for the change in subhalo mass. We conclude that predictions for galaxy-galaxy and galaxy-mass clustering from models based on dark matter only simulations will have errors greater than 10% on sub-Mpc scales, unless the simulation results are modified to correctly account for the effects of baryons on the distributions of mass and satellites.}, added-at = {2013-10-30T08:48:53.000+0100}, author = {van Daalen, Marcel P. and Schaye, Joop and McCarthy, Ian G. and Booth, C. M. and Vecchia, Claudio Dalla}, biburl = {https://www.bibsonomy.org/bibtex/2cb2ffa009bd1dfa2fa2b00da1b76a5f5/miki}, description = {[1310.7571] The impact of baryonic processes on the two-point correlation functions of galaxies, subhaloes and matter}, interhash = {eee8e31aaf13c13ee840b28d93e361fa}, intrahash = {cb2ffa009bd1dfa2fa2b00da1b76a5f5}, keywords = {baryon correlation function galaxy}, note = {cite arxiv:1310.7571Comment: 15 pages, 9 figures. Submitted to MNRAS}, timestamp = {2013-10-30T08:48:53.000+0100}, title = {The impact of baryonic processes on the two-point correlation functions of galaxies, subhaloes and matter}, url = {http://arxiv.org/abs/1310.7571}, year = 2013 }