%0 Generic %1 cote2017validating %A Côté, Benoit %A Silvia, Devin %A O'Shea, Brian W. %A Smith, Britton %A Wise, John H. %D 2017 %K SAM galaxies high-z hydrodynamic simulations %T Validating Semi-Analytic Models of High-Redshift Galaxy Formation using Radiation Hydrodynamical Simulations %U http://arxiv.org/abs/1710.06442 %X We use a cosmological hydrodynamic simulation calculated with Enzo and the semi-analytic galaxy formation model (SAM) GAMMA to address the chemical evolution of dwarf galaxies in the early universe. The overall goal is to better understand the origin of metal-poor stars and the formation of dwarf galaxies and the Milky Way halo by cross-validating these theoretical approaches. We combine GAMMA with the merger tree of the most massive galaxy found in the hydrodynamic simulation and compare the star formation rate, the metallicity distribution function (MDF), and the age-metallicity relationship predicted by the two approaches. We found that the SAM can reproduce the global trends of the hydrodynamic simulation. However, there are degeneracies and more constraints need to be extracted from the simulation to isolate the correct semi-analytic solution. Non-uniform mixing in the galaxy's interstellar medium, coming primarily from self-enrichment by local supernovae, causes a broadening in the MDF that can be emulated in the SAM by convolving its predicted MDF with a Gaussian function having a standard deviation of $\sim$0.2 dex. However, stochastic processes such as bursty star formation histories and star formation triggered by supernova explosions cannot be reproduced by the current version of GAMMA. Moreover, we found that massive stars in building-block galaxies tend to explode and generate outflows while falling inside the main galaxy's halo, leading to a complex multiphase circumgalactic medium with a wide range of temperatures, densities, and metallicities, as opposed to the hot, isothermal, well-mixed halo gas in equilibrium assumed in SAMs.

@misc{cote2017validating, abstract = {We use a cosmological hydrodynamic simulation calculated with Enzo and the semi-analytic galaxy formation model (SAM) GAMMA to address the chemical evolution of dwarf galaxies in the early universe. The overall goal is to better understand the origin of metal-poor stars and the formation of dwarf galaxies and the Milky Way halo by cross-validating these theoretical approaches. We combine GAMMA with the merger tree of the most massive galaxy found in the hydrodynamic simulation and compare the star formation rate, the metallicity distribution function (MDF), and the age-metallicity relationship predicted by the two approaches. We found that the SAM can reproduce the global trends of the hydrodynamic simulation. However, there are degeneracies and more constraints need to be extracted from the simulation to isolate the correct semi-analytic solution. Non-uniform mixing in the galaxy's interstellar medium, coming primarily from self-enrichment by local supernovae, causes a broadening in the MDF that can be emulated in the SAM by convolving its predicted MDF with a Gaussian function having a standard deviation of $\sim$0.2 dex. However, stochastic processes such as bursty star formation histories and star formation triggered by supernova explosions cannot be reproduced by the current version of GAMMA. Moreover, we found that massive stars in building-block galaxies tend to explode and generate outflows while falling inside the main galaxy's halo, leading to a complex multiphase circumgalactic medium with a wide range of temperatures, densities, and metallicities, as opposed to the hot, isothermal, well-mixed halo gas in equilibrium assumed in SAMs.}, added-at = {2017-10-19T09:58:36.000+0200}, author = {Côté, Benoit and Silvia, Devin and O'Shea, Brian W. and Smith, Britton and Wise, John H.}, biburl = {https://www.bibsonomy.org/bibtex/2bea74063bb1c73c910da275f95ddbd1c/miki}, description = {[1710.06442] Validating Semi-Analytic Models of High-Redshift Galaxy Formation using Radiation Hydrodynamical Simulations}, interhash = {72c81c73d88642da52aae6c9168c92a0}, intrahash = {bea74063bb1c73c910da275f95ddbd1c}, keywords = {SAM galaxies high-z hydrodynamic simulations}, note = {cite arxiv:1710.06442Comment: 19 pages, 12 figures, 2 tables, submitted to ApJ}, timestamp = {2017-10-19T09:58:36.000+0200}, title = {Validating Semi-Analytic Models of High-Redshift Galaxy Formation using Radiation Hydrodynamical Simulations}, url = {http://arxiv.org/abs/1710.06442}, year = 2017 }