English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

To investigate the evolution of metal-enriched gas over recent cosmic epochsas well as to characterize the diffuse, ionized, metal-enriched circumgalacticmedium (CGM), we have conducted a blind survey for C IV absorption systems in89 QSO sightlines observed with the Hubble Space Telescope (HST) Cosmic OriginsSpectrograph (COS). We have identified 42 absorbers at z < 0.16, comprising thelargest uniform blind sample size to date in this redshift range. Ourmeasurements indicate an increasing C IV absorber number density per comovingpath length (dN/dX = 7.5 +/- 1.1) and modestly increasing mass density relativeto the critical density of the Universe (Omega(C IV) = 10.0 +/- 1.5 x 10^-8 )from z ~ 1.5 to the present epoch, consistent with predictions fromcosmological hydrodynamical simulations. Furthermore, the data support afunctional form for the column density distribution function that deviates froma single power-law, also consistent with independent theoretical predictions.As the data also probe heavy element ions in addition to C IV at the sameredshifts, we identify, measure, and search for correlations between columndensities of these species where components appear aligned in velocity. Amongthese ion-ion correlations, we find evidence for tight correlations between CII and Si II, C II and Si III, and C IV and Si IV, suggesting that these pairsof species arise in similar ionization conditions. However, the evidence forcorrelations decreases as the difference in ionization potential increases.Finally, when controlling for observational bias, we find only marginalevidence for a correlation (86.8% likelihood) between the Doppler line widthb(C IV) and column density N(C IV).

astrophysical journal/the astrophysical journal

A Deep Search For Faint Galaxies Associated With Very Low-redshift C IV  Absorbers: II. Program Design, Absorption-line Measurements, and Absorber  Statistics