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Budget And Accounting Of Metals At Z~0: Results From The Cos-Halos Survey, Molly S. Peeples, Jessica K. Werk, Jason Tumlinson, Benjamin D. Oppenheimer, J. Xavier Prochaska, Neal S. Katz, David H. Weinberg
Budget And Accounting Of Metals At Z~0: Results From The Cos-Halos Survey, Molly S. Peeples, Jessica K. Werk, Jason Tumlinson, Benjamin D. Oppenheimer, J. Xavier Prochaska, Neal S. Katz, David H. Weinberg
Neal S. Katz
We present a budget and accounting of metals in and around star-forming galaxies at z ~ 0. We combine empirically derived star formation histories with updated supernova and asymptotic giant branch yields and rates to estimate the total mass of metals produced by galaxies with present-day stellar mass of 109.3-1011.6 M☉. On the accounting side of the ledger, we show that a surprisingly constant 20%-25% mass fraction of produced metals remain in galaxies' stars, interstellar gas and interstellar dust, with little dependence of this fraction on the galaxy stellar mass (omitting those metals immediately locked up in remnants). Thus, the …
The Photon Underproduction Crisis, Juna A. Kollmeier, David H. Weinberg, Benjamin D. Oppenheimer, Francesco Haardt, Neal S. Katz, Rameel A. Dave, Mark Fardal, Piero Madau, Charles Danforth, Amanda B. Ford, Molly S. Peeples, Joseph Mcewen
The Photon Underproduction Crisis, Juna A. Kollmeier, David H. Weinberg, Benjamin D. Oppenheimer, Francesco Haardt, Neal S. Katz, Rameel A. Dave, Mark Fardal, Piero Madau, Charles Danforth, Amanda B. Ford, Molly S. Peeples, Joseph Mcewen
Neal S. Katz
We examine the statistics of the low-redshift Lyα forest from smoothed particle hydrodynamic simulations in light of recent improvements in the estimated evolution of the cosmic ultraviolet background (UVB) and recent observations from the Cosmic Origins Spectrograph (COS). We find that the value of the metagalactic photoionization rate (ΓHI) required by our simulations to match the observed properties of the low-redshift Lyα forest is a factor of five larger than the value predicted by state-of-the art models for the evolution of this quantity. This mismatch in ΓHI results in the mean flux decrement of the Lyα forest being overpredicted by …
The Cos-Halos Survey: Physical Conditions And Baryonic Mass In The Low-Redshift Circumgalactic Medium, Jessica K. Werk, J. Xavier Prochaska, Jason Tumlinson, Molly S. Peeples, Todd M. Tripp, Andrew J. Fox, Nicolas Lehner, Christopher Thom, John M. O'Meara, Amanda Brady Ford, Rongmon Bordoloi, Neal S. Katz, Nicolas Tejos, Benjamin D. Oppenheimer, Romeel Dave, David H. Weinberg
The Cos-Halos Survey: Physical Conditions And Baryonic Mass In The Low-Redshift Circumgalactic Medium, Jessica K. Werk, J. Xavier Prochaska, Jason Tumlinson, Molly S. Peeples, Todd M. Tripp, Andrew J. Fox, Nicolas Lehner, Christopher Thom, John M. O'Meara, Amanda Brady Ford, Rongmon Bordoloi, Neal S. Katz, Nicolas Tejos, Benjamin D. Oppenheimer, Romeel Dave, David H. Weinberg
Neal S. Katz
We analyze the physical conditions of the cool, photoionized (T ~104 K) circumgalactic medium (CGM) using the COS-Halos suite of gas column density measurements for 44 gaseous halos within 160 kpc of L ~ L* galaxies at z ~ 0.2. These data are well described by simple photoionization models, with the gas highly ionized (n H II /n H gsim 99%) by the extragalactic ultraviolet background. Scaling by estimates for the virial radius, R vir, we show that the ionization state (tracked by the dimensionless ionization parameter, U) increases with distance from the host galaxy. The ionization parameters imply a …
The Cos-Dwarfs Survey: The Carbon Reservoir Around Sub-L Galaxies, Rongmon Bordoloi, Jason Tumlinson, Jessica K. Werk, Benjamin D. Oppenheimer, Molly S. Peeples, J. Xavier Prochaska, Todd M. Tripp, Neal S. Katz, Romeel Dave, Andrew J. Fox, Christopher Thom, Amanda Brady Ford, David H. Weinberg, Joseph N. Burchett, Juna A. Kollmeier
The Cos-Dwarfs Survey: The Carbon Reservoir Around Sub-L Galaxies, Rongmon Bordoloi, Jason Tumlinson, Jessica K. Werk, Benjamin D. Oppenheimer, Molly S. Peeples, J. Xavier Prochaska, Todd M. Tripp, Neal S. Katz, Romeel Dave, Andrew J. Fox, Christopher Thom, Amanda Brady Ford, David H. Weinberg, Joseph N. Burchett, Juna A. Kollmeier
Neal S. Katz
We report new observations of circumgalactic gas from the COS-Dwarfs survey, a systematic investigation of the gaseous halos around 43 low-mass z ≤ 0.1 galaxies using background QSOs observed with the Cosmic Origins Spectrograph. From the projected one-dimensional and two-dimensional distribution of C iv absorption, we find that C iv is detected out to ≈100 kpc (corresponding roughly to ≈0.5 Rvir) of the host galaxies. The C iv absorption strength falls off radially as a power law, and beyond ≈0.5 Rvir, no C iv absorption is detected above our sensitivity limit of ≈50–100 mÅ. We find a tentative correlation between …
The Cos-Halos Survey: Rationale, Design, And A Census Of Circumgalactic Neutral Hydrogen, Jason Tumlinson, Christopher Thom, Jessica K. Werk, J. Xavier Prochaska, Todd M. Tripp, Neal S. Katz, Romeel Dave, Benjamin D. Oppenheimer, Joseph D. Meiring, Amanda Brady Ford, John M. O'Meara, Molly S. Peeples, Kenneth R. Sembach, David H. Weinberg
The Cos-Halos Survey: Rationale, Design, And A Census Of Circumgalactic Neutral Hydrogen, Jason Tumlinson, Christopher Thom, Jessica K. Werk, J. Xavier Prochaska, Todd M. Tripp, Neal S. Katz, Romeel Dave, Benjamin D. Oppenheimer, Joseph D. Meiring, Amanda Brady Ford, John M. O'Meara, Molly S. Peeples, Kenneth R. Sembach, David H. Weinberg
Neal S. Katz
We present the design and methods of the COS-Halos survey, a systematic investigation of the gaseous halos of 44 z = 0.15-0.35 galaxies using background QSOs observed with the Cosmic Origins Spectrograph aboard the Hubble Space Telescope. This survey has yielded 39 spectra of z em sime 0.5 QSOs with S/N ~10-15 per resolution element. The QSO sightlines pass within 150 physical kpc of the galaxies, which span early and late types over stellar mass log M */M ☉ = 9.5-11.5. We find that the circumgalactic medium exhibits strong H I, averaging sime 1 Å in Lyα equivalent width out …
The High-Ion Content And Kinematics Of Low-Redshift Lyman Limit Systems, Andrew J. Fox, Nicolas Lehner, Jason Tumlinson, J. Christopher Howk, Todd M. Tripp, J. Xavier Prochaska, John M. O'Meara, Jessica K. Werk, Rognmon Bordoloi, Neal S. Katz, Benjamin D. Oppenheimer, Romeel Dave
The High-Ion Content And Kinematics Of Low-Redshift Lyman Limit Systems, Andrew J. Fox, Nicolas Lehner, Jason Tumlinson, J. Christopher Howk, Todd M. Tripp, J. Xavier Prochaska, John M. O'Meara, Jessica K. Werk, Rognmon Bordoloi, Neal S. Katz, Benjamin D. Oppenheimer, Romeel Dave
Neal S. Katz
We study the high-ion content and kinematics of the circumgalactic medium around low-redshift galaxies using a sample of 23 Lyman limit systems (LLSs) at 0.08 < z < 0.93 observed with the Cosmic Origins Spectrograph on board the Hubble Space Telescope. In Lehner et al., we recently showed that low-z LLSs have a bimodal metallicity distribution. Here we extend that analysis to search for differences between the high-ion and kinematic properties of the metal-poor and metal-rich branches. We find that metal-rich LLSs tend to show higher O VI columns and broader O VI profiles than metal-poor LLSs. The total H I line width (Δv 90 statistic) in LLSs is not correlated with metallicity, indicating that the H I kinematics alone cannot be used to distinguish inflow from outflow and gas recycling. Among the 17 LLSs with O VI detections, all but two show evidence of kinematic sub-structure, in the form of O VI-H I centroid offsets, multiple components, or both. Using various scenarios for how the metallicities in the high-ion and low-ion phases of each LLS compare, we constrain the ionized hydrogen column in the O VI phase to lie in the range log N(H II) ~ 17.6-20. The O VI phase of LLSs is a substantial baryon reservoir, with M(high-ion) ~ 108.5-10.9 (r/150 kpc)2 M ☉, similar to the mass in the low-ion phase. Accounting for the O VI phase approximately doubles the contribution of low-z LLSs to the cosmic baryon budget.