Related papers: Metallicity and Quasar Outflows
There are mutually contradictory views in the literature of the kinematics and structure of high-ionization line (e.g. CIV) emitting regions in active galactic nuclei (AGNs). Two kinds of broad emission line region (BELR) models have been…
Cosmic metal enrichment is one of the key physical processes regulating galaxy formation and the evolution of the intergalactic medium (IGM). However, determining the metal content of the most distant galaxies has proven so far almost…
Generally the gas metallicity in distant galaxies can only be inferred by using a few prominent emission lines. Various theoretical models have been used to predict the relationship between emission line fluxes and metallicity, suggesting…
Interpreting the scaling relations followed by galaxies is a fundamental tool for assessing how well we understand galaxy formation and evolution. Several scaling relations involving the galaxy metallicity have been discovered through the…
The metal content of a galaxy is a key property for distinguishing between viable galaxy evolutionary scenarios, and it strongly influences many of the physical processes in the interstellar medium. An absolute and robust determination of…
Using a sample of 30,000 quasars from SDSS-DR7, we explore the range of properties exhibited by high-ionization, broad emission lines, such as CIV 1549. Specifically we investigate the anti-correlation between L_UV and emission line EQW…
We isolate a set of quasars that exhibit emergent C iv broad absorption lines (BALs) in their spectra by comparing spectra in the SDSS Data Release 7 and the SDSS/BOSS Data Releases 9 and 10. After visually defining a set of emergent BALs,…
An analytical chemical evolution model is constructed to investigate the radial distribution of gas-phase and stellar metallicity for star-forming galaxies. By means of the model, the gas-phase and stellar metallicity can be obtained from…
Nuclear inflows of metal-poor interstellar gas triggered by galaxy interactions can account for the systematically lower central oxygen abundances observed in local interacting galaxies. Here, we investigate the metallicity evolution of a…
We investigate the evolution of the ionization state of metal-enriched gas in and around galaxies near the epoch of reionization using a sample of 488 metal absorption systems at 4.3<z<6.3 from the E-XQR-30 survey. We classify the…
(Abridged) Using cosmological hydrodynamic simulations in combination with analytic modeling, we show that the galaxy stellar mass-metallicity relation (MZR) provides strong constraints on galactic outflows across cosmic time. We compare…
I Zw 1 is the prototype narrow line quasar. We report here the results of our study of the UV emission of I Zw 1 using a high S/N (50-120) spectrum obtained with the HST FOS. The following main new results are obtained: 1. The Mg II and Al…
The analysis of the chemical composition of galaxies provides fundamental insights into their evolution. This holds true also in the case of the outer regions of spiral galaxies. This Chapter presents the observational data, accumulated in…
The ratios of strong rest-frame optical emission lines are the dominant indicator of metallicities in high-redshift galaxies. Since typical strong-line based metallicity indicators are calibrated on auroral lines at $z=0$, their…
We present [CII] 158um measurements from over 15,000 resolved regions within 54 nearby galaxies of the KINGFISH program to investigate the so-called [CII] "line cooling deficit" long known to occur in galaxies with different luminosities.…
Observations of infrared fine-structure lines provide direct information on the metallicity and ionization structure of HII regions and indirectly on the hardness of the radiation field ionizing these nebulae. We have analyzed a sample of…
The \textit{JWST} is allowing new measurements of gas-phase metallicities in galaxies between cosmic noon and cosmic dawn. The most robust approach uses luminosity ratios between the excited auroral transition, [\oiii] 4364\,\AA, and the…
The gas-phase metallicity distribution has been analyzed for the hot atmospheres of 29 galaxy clusters using {\it Chandra X-ray Observatory} observations. All host brightest cluster galaxies (BCGs) with X-ray cavity systems produced by…
The iron abundance relative to alpha-elements in the circumnuclear region of quasars is regarded as a clock of the star formation history and, more specifically, of the enrichment by SNIa. We investigate the iron abundance in a sample of 22…
We study the relation between nitrogen and oxygen abundances as a function of metallicity for a sample of emission-line objects for which a direct measurement of the metallicity has been possible. This sample is representative of the very…