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Articles 1 - 4 of 4
Full-Text Articles in Physical Sciences and Mathematics
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 …