@article{oppenheimer_multiphase_2017,
	title = {The multiphase circumgalactic medium traced by low metal ions in {EAGLE} zoom simulations},
	volume = {1709},
	url = {http://adsabs.harvard.edu/abs/2017arXiv170907577O},
	abstract = {We explore the circumgalactic metal content traced by commonly observed 
low ion absorbers, including C II, Si II, Si III, Si IV, and Mg II. We
use a set of cosmological hydrodynamical zoom simulations run with the
EAGLE model and including a non-equilibrium ionization and cooling
module that follows 136 ions. The simulations of z{\textasciitilde}0.2 L*
(M\_200=10{\textasciicircum}11.7-10{\textasciicircum}12.3 Msol) haloes hosting star-forming galaxies and
group-sized (M\_200=10{\textasciicircum}12.7-10{\textasciicircum}13.3 Msol) haloes hosting mainly passive
galaxies reproduce key trends observed by the COS-Halos survey-- low ion
column densities show 1) little dependence on galaxy specific star
formation rate, 2) a patchy covering fraction indicative of 10{\textasciicircum}4 K
clouds with a small volume filling factor, and 3) a declining covering
fraction as impact parameter increases from 20-160 kpc. Simulated Si II,
Si III, Si IV, C II, and C III column densities show good agreement with
observations, while Mg II is under-predicted. Low ions trace a
significant metal reservoir, {\textasciitilde}10{\textasciicircum}8 Msol, residing primarily at 10-100
kpc from star-forming and passive central galaxies. These clouds tend to
flow inwards and most will accrete onto the central galaxy within the
next several Gyr, while a small fraction are entrained in strong
outflows. A two-phase structure describes the inner CGM ({\textless}0.5 R\_200)
with low-ion metal clouds surrounded by a hot, ambient medium. This cool
phase is separate from the O VI observed by COS-Halos, which arises from
the outer CGM ({\textgreater}0.5 R\_200) tracing virial temperature gas around L*
galaxies. Physical parameters derived from standard photo-ionization
modelling of observed column densities (e.g. aligned Si II/Si III
absorbers) are validated against our simulations. Our simulations
therefore support previous ionization models indicating that cloud
covering factors decline while densities and pressures show little
variation with increasing impact parameter.},
	journal = {ArXiv e-prints},
	author = {Oppenheimer, Benjamin D. and Schaye, Joop and Crain, Robert A. and Werk, Jessica K. and Richings, Alexander J.},
	month = sep,
	year = {2017},
	keywords = {Astrophysics - Astrophysics of Galaxies},
	pages = {arXiv:1709.07577},
}

{"_id":"3Mb36HuWSfnGrAYHL","bibbaseid":"oppenheimer-schaye-crain-werk-richings-themultiphasecircumgalacticmediumtracedbylowmetalionsineaglezoomsimulations-2017","author_short":["Oppenheimer, B. D.","Schaye, J.","Crain, R. A.","Werk, J. K.","Richings, A. J."],"bibdata":{"bibtype":"article","type":"article","title":"The multiphase circumgalactic medium traced by low metal ions in EAGLE zoom simulations","volume":"1709","url":"http://adsabs.harvard.edu/abs/2017arXiv170907577O","abstract":"We explore the circumgalactic metal content traced by commonly observed low ion absorbers, including C II, Si II, Si III, Si IV, and Mg II. We use a set of cosmological hydrodynamical zoom simulations run with the EAGLE model and including a non-equilibrium ionization and cooling module that follows 136 ions. The simulations of z\\textasciitilde0.2 L* (M_200=10\\textasciicircum11.7-10\\textasciicircum12.3 Msol) haloes hosting star-forming galaxies and group-sized (M_200=10\\textasciicircum12.7-10\\textasciicircum13.3 Msol) haloes hosting mainly passive galaxies reproduce key trends observed by the COS-Halos survey– low ion column densities show 1) little dependence on galaxy specific star formation rate, 2) a patchy covering fraction indicative of 10\\textasciicircum4 K clouds with a small volume filling factor, and 3) a declining covering fraction as impact parameter increases from 20-160 kpc. Simulated Si II, Si III, Si IV, C II, and C III column densities show good agreement with observations, while Mg II is under-predicted. Low ions trace a significant metal reservoir, \\textasciitilde10\\textasciicircum8 Msol, residing primarily at 10-100 kpc from star-forming and passive central galaxies. These clouds tend to flow inwards and most will accrete onto the central galaxy within the next several Gyr, while a small fraction are entrained in strong outflows. A two-phase structure describes the inner CGM (\\textless0.5 R_200) with low-ion metal clouds surrounded by a hot, ambient medium. This cool phase is separate from the O VI observed by COS-Halos, which arises from the outer CGM (\\textgreater0.5 R_200) tracing virial temperature gas around L* galaxies. Physical parameters derived from standard photo-ionization modelling of observed column densities (e.g. aligned Si II/Si III absorbers) are validated against our simulations. Our simulations therefore support previous ionization models indicating that cloud covering factors decline while densities and pressures show little variation with increasing impact parameter.","journal":"ArXiv e-prints","author":[{"propositions":[],"lastnames":["Oppenheimer"],"firstnames":["Benjamin","D."],"suffixes":[]},{"propositions":[],"lastnames":["Schaye"],"firstnames":["Joop"],"suffixes":[]},{"propositions":[],"lastnames":["Crain"],"firstnames":["Robert","A."],"suffixes":[]},{"propositions":[],"lastnames":["Werk"],"firstnames":["Jessica","K."],"suffixes":[]},{"propositions":[],"lastnames":["Richings"],"firstnames":["Alexander","J."],"suffixes":[]}],"month":"September","year":"2017","keywords":"Astrophysics - Astrophysics of Galaxies","pages":"arXiv:1709.07577","bibtex":"@article{oppenheimer_multiphase_2017,\n\ttitle = {The multiphase circumgalactic medium traced by low metal ions in {EAGLE} zoom simulations},\n\tvolume = {1709},\n\turl = {http://adsabs.harvard.edu/abs/2017arXiv170907577O},\n\tabstract = {We explore the circumgalactic metal content traced by commonly observed \nlow ion absorbers, including C II, Si II, Si III, Si IV, and Mg II. We\nuse a set of cosmological hydrodynamical zoom simulations run with the\nEAGLE model and including a non-equilibrium ionization and cooling\nmodule that follows 136 ions. The simulations of z{\\textasciitilde}0.2 L*\n(M\\_200=10{\\textasciicircum}11.7-10{\\textasciicircum}12.3 Msol) haloes hosting star-forming galaxies and\ngroup-sized (M\\_200=10{\\textasciicircum}12.7-10{\\textasciicircum}13.3 Msol) haloes hosting mainly passive\ngalaxies reproduce key trends observed by the COS-Halos survey-- low ion\ncolumn densities show 1) little dependence on galaxy specific star\nformation rate, 2) a patchy covering fraction indicative of 10{\\textasciicircum}4 K\nclouds with a small volume filling factor, and 3) a declining covering\nfraction as impact parameter increases from 20-160 kpc. Simulated Si II,\nSi III, Si IV, C II, and C III column densities show good agreement with\nobservations, while Mg II is under-predicted. Low ions trace a\nsignificant metal reservoir, {\\textasciitilde}10{\\textasciicircum}8 Msol, residing primarily at 10-100\nkpc from star-forming and passive central galaxies. These clouds tend to\nflow inwards and most will accrete onto the central galaxy within the\nnext several Gyr, while a small fraction are entrained in strong\noutflows. A two-phase structure describes the inner CGM ({\\textless}0.5 R\\_200)\nwith low-ion metal clouds surrounded by a hot, ambient medium. This cool\nphase is separate from the O VI observed by COS-Halos, which arises from\nthe outer CGM ({\\textgreater}0.5 R\\_200) tracing virial temperature gas around L*\ngalaxies. Physical parameters derived from standard photo-ionization\nmodelling of observed column densities (e.g. aligned Si II/Si III\nabsorbers) are validated against our simulations. Our simulations\ntherefore support previous ionization models indicating that cloud\ncovering factors decline while densities and pressures show little\nvariation with increasing impact parameter.},\n\tjournal = {ArXiv e-prints},\n\tauthor = {Oppenheimer, Benjamin D. and Schaye, Joop and Crain, Robert A. and Werk, Jessica K. and Richings, Alexander J.},\n\tmonth = sep,\n\tyear = {2017},\n\tkeywords = {Astrophysics - Astrophysics of Galaxies},\n\tpages = {arXiv:1709.07577},\n}\n\n","author_short":["Oppenheimer, B. D.","Schaye, J.","Crain, R. A.","Werk, J. K.","Richings, A. J."],"key":"oppenheimer_multiphase_2017","id":"oppenheimer_multiphase_2017","bibbaseid":"oppenheimer-schaye-crain-werk-richings-themultiphasecircumgalacticmediumtracedbylowmetalionsineaglezoomsimulations-2017","role":"author","urls":{"Paper":"http://adsabs.harvard.edu/abs/2017arXiv170907577O"},"keyword":["Astrophysics - Astrophysics of Galaxies"],"metadata":{"authorlinks":{}}},"bibtype":"article","biburl":"https://bibbase.org/zotero/polyphant","dataSources":["7gvjSdWrEu7z5vjjj"],"keywords":["astrophysics - astrophysics of galaxies"],"search_terms":["multiphase","circumgalactic","medium","traced","low","metal","ions","eagle","zoom","simulations","oppenheimer","schaye","crain","werk","richings"],"title":"The multiphase circumgalactic medium traced by low metal ions in EAGLE zoom simulations","year":2017}