We present an analysis of the flow of metals through the circumgalactic
medium in the Feedback in Realistic Environments (FIRE) simulations of galaxy
formation, ranging from isolated dwarfs to $L*$. We find that nearly all metals
produced in high-redshift galaxies are carried out in winds that escape the
galaxy and reach $0.25 R_vir$. When measured at $0.25 R_vir$ the
metallicity of outflows is greater than, but similar to the ISM metallicity.
Many metals thus reside in a reservoir in the CGM. We find that the outflowing
flux through $R_vir$ is lower than that at $0.25 R_vir$ by a factor
of $\sim2-5$. Cooling and recycling from this reservoir determine the metal
budget in the ISM. The inflow metallicity at $R_vir$ is generally very
low, but outflow and inflow metallicities are similar in the inner halo. At low
redshift, massive galaxies no longer generate outflows that reach the CGM,
causing a divergence in CGM and ISM metallicity. Dwarf galaxies continue to
generate outflows, which become increasingly dominated by metal-poor gas, while
the galaxies themselves preferentially retains metal ejecta. In all but the
least massive galaxy considered, a majority of the metals are within the halo
at $z=0$. We measure the fraction of metals in CGM, ISM, stars, and roughly
quantify the thermal state of CGM metals in each halo. The total amount of
metals in the low-redshift CGM of two simulated L* galaxies is consistent with
estimates from the COS halos survey, while for the other two it appears to be
lower.
%0 Generic
%1 muratov2016metal
%A Muratov, Alexander L.
%A Keres, Dusan
%A Faucher-Giguere, Claude-Andre
%A Hopkins, Philip F.
%A Ma, Xiangcheng
%A Angles-Alcazar, Daniel
%A Chan, T. K.
%A Torrey, Paul
%A Hafen, Zachary H.
%A Quataert, Eliot
%A Murray, Norman
%D 2016
%K inflow metal outflow simulation
%T Metal flows of the circumgalactic medium, and the metal budget in
galactic halos
%U http://arxiv.org/abs/1606.09252
%X We present an analysis of the flow of metals through the circumgalactic
medium in the Feedback in Realistic Environments (FIRE) simulations of galaxy
formation, ranging from isolated dwarfs to $L*$. We find that nearly all metals
produced in high-redshift galaxies are carried out in winds that escape the
galaxy and reach $0.25 R_vir$. When measured at $0.25 R_vir$ the
metallicity of outflows is greater than, but similar to the ISM metallicity.
Many metals thus reside in a reservoir in the CGM. We find that the outflowing
flux through $R_vir$ is lower than that at $0.25 R_vir$ by a factor
of $\sim2-5$. Cooling and recycling from this reservoir determine the metal
budget in the ISM. The inflow metallicity at $R_vir$ is generally very
low, but outflow and inflow metallicities are similar in the inner halo. At low
redshift, massive galaxies no longer generate outflows that reach the CGM,
causing a divergence in CGM and ISM metallicity. Dwarf galaxies continue to
generate outflows, which become increasingly dominated by metal-poor gas, while
the galaxies themselves preferentially retains metal ejecta. In all but the
least massive galaxy considered, a majority of the metals are within the halo
at $z=0$. We measure the fraction of metals in CGM, ISM, stars, and roughly
quantify the thermal state of CGM metals in each halo. The total amount of
metals in the low-redshift CGM of two simulated L* galaxies is consistent with
estimates from the COS halos survey, while for the other two it appears to be
lower.
@misc{muratov2016metal,
abstract = {We present an analysis of the flow of metals through the circumgalactic
medium in the Feedback in Realistic Environments (FIRE) simulations of galaxy
formation, ranging from isolated dwarfs to $L*$. We find that nearly all metals
produced in high-redshift galaxies are carried out in winds that escape the
galaxy and reach $0.25 R_{\rm vir}$. When measured at $0.25 R_{\rm vir}$ the
metallicity of outflows is greater than, but similar to the ISM metallicity.
Many metals thus reside in a reservoir in the CGM. We find that the outflowing
flux through $R_{\rm vir}$ is lower than that at $0.25 R_{\rm vir}$ by a factor
of $\sim2-5$. Cooling and recycling from this reservoir determine the metal
budget in the ISM. The inflow metallicity at $R_{\rm vir}$ is generally very
low, but outflow and inflow metallicities are similar in the inner halo. At low
redshift, massive galaxies no longer generate outflows that reach the CGM,
causing a divergence in CGM and ISM metallicity. Dwarf galaxies continue to
generate outflows, which become increasingly dominated by metal-poor gas, while
the galaxies themselves preferentially retains metal ejecta. In all but the
least massive galaxy considered, a majority of the metals are within the halo
at $z=0$. We measure the fraction of metals in CGM, ISM, stars, and roughly
quantify the thermal state of CGM metals in each halo. The total amount of
metals in the low-redshift CGM of two simulated L* galaxies is consistent with
estimates from the COS halos survey, while for the other two it appears to be
lower.},
added-at = {2016-07-06T10:06:51.000+0200},
author = {Muratov, Alexander L. and Keres, Dusan and Faucher-Giguere, Claude-Andre and Hopkins, Philip F. and Ma, Xiangcheng and Angles-Alcazar, Daniel and Chan, T. K. and Torrey, Paul and Hafen, Zachary H. and Quataert, Eliot and Murray, Norman},
biburl = {https://www.bibsonomy.org/bibtex/26a6e82994d10abdd4b9ecc52ef72c1fc/miki},
interhash = {5cfe07c3349fd72e1d28cbab6faaedcd},
intrahash = {6a6e82994d10abdd4b9ecc52ef72c1fc},
keywords = {inflow metal outflow simulation},
note = {cite arxiv:1606.09252Comment: 18 Pages, 14 Figures, Submitted to MNRAS, comments welcome},
timestamp = {2016-07-06T10:06:51.000+0200},
title = {Metal flows of the circumgalactic medium, and the metal budget in
galactic halos},
url = {http://arxiv.org/abs/1606.09252},
year = 2016
}