%0 Generic %1 ubler2014stellar %A Übler, Hannah %A Naab, Thorsten %A Oser, Ludwig %A Aumer, Michael %A Sales, Laura V. %A White, Simon %D 2014 %K disk feedback formation %T Why stellar feedback promotes disc formation in simulated galaxies %U http://arxiv.org/abs/1403.6124 %X We study how feedback influences baryon infall onto galaxies using cosmological, zoom-in simulations of haloes with present mass $M_vir=6.9\times10^11 M_ødot$ to $1.7\times10^12 M_ødot$. Starting at $z=4$ from identical initial conditions, implementations of weak and strong stellar feedback produce bulge- and disc-dominated galaxies, respectively. Strong feedback favours disc formation: (1) because conversion of gas into stars is suppressed at early times, as required by abundance matching arguments, resulting in flat star formation histories and higher gas fractions; (2) because $50\%$ of the stars form $in$ $situ$ from recycled disc gas with angular momentum only weakly related to that of the $z=0$ dark halo; (3) because late-time gas accretion is typically an order of magnitude stronger and has higher specific angular momentum, with recycled gas dominating over primordial infall; (4) because $25-30\%$ of the total accreted gas is ejected entirely before $z\sim1$, removing primarily low angular momentum material which enriches the nearby inter-galactic medium. Most recycled gas roughly conserves its angular momentum, but material ejected for long times and to large radii can gain significant angular momentum before re-accretion. These processes lower galaxy formation efficiency in addition to promoting disc formation.

@misc{ubler2014stellar, abstract = {We study how feedback influences baryon infall onto galaxies using cosmological, zoom-in simulations of haloes with present mass $\mathrm{M}_{\mathrm{vir}}=6.9\times10^{11} \mathrm{M}_{\odot}$ to $1.7\times10^{12} \mathrm{M}_{\odot}$. Starting at $z=4$ from identical initial conditions, implementations of weak and strong stellar feedback produce bulge- and disc-dominated galaxies, respectively. Strong feedback favours disc formation: (1) because conversion of gas into stars is suppressed at early times, as required by abundance matching arguments, resulting in flat star formation histories and higher gas fractions; (2) because $50\%$ of the stars form ${\it in}$ ${\it situ}$ from recycled disc gas with angular momentum only weakly related to that of the $z=0$ dark halo; (3) because late-time gas accretion is typically an order of magnitude stronger and has higher specific angular momentum, with recycled gas dominating over primordial infall; (4) because $25-30\%$ of the total accreted gas is ejected entirely before $z\sim1$, removing primarily low angular momentum material which enriches the nearby inter-galactic medium. Most recycled gas roughly conserves its angular momentum, but material ejected for long times and to large radii can gain significant angular momentum before re-accretion. These processes lower galaxy formation efficiency in addition to promoting disc formation.}, added-at = {2014-03-26T09:53:46.000+0100}, author = {Übler, Hannah and Naab, Thorsten and Oser, Ludwig and Aumer, Michael and Sales, Laura V. and White, Simon}, biburl = {https://www.bibsonomy.org/bibtex/24cbd7193572e97d6c9bd2feebbbaf525/miki}, description = {[1403.6124] Why stellar feedback promotes disc formation in simulated galaxies}, interhash = {b9ce3fdafef57ec948bb0df9c2ccce8e}, intrahash = {4cbd7193572e97d6c9bd2feebbbaf525}, keywords = {disk feedback formation}, note = {cite arxiv:1403.6124Comment: submitted; comments are welcome}, timestamp = {2014-03-26T09:53:46.000+0100}, title = {Why stellar feedback promotes disc formation in simulated galaxies}, url = {http://arxiv.org/abs/1403.6124}, year = 2014 }