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

We present an analysis of asymmetries in global HI spectra from the extendedGALEX Arecibo SDSS Survey (xGASS), a stellar mass-selected and gasfraction-limited survey which is representative of the HI properties ofgalaxies in the local Universe. We demonstrate that the asymmetry in a HIspectrum is strongly linked to its signal-to-noise meaning that, contrary towhat was done in previous works, asymmetry distributions for different samplescannot be compared at face value. We develop a method to account fornoise-induced asymmetry and find that the typical galaxy detected by xGASSexhibits higher asymmetry than what can be attributed to noise alone, with 37%of the sample showing asymmetry greater than 10% at an 80% confidence level. Wefind that asymmetric galaxies contain, on average, 29% less HI mass compared totheir symmetric counterparts matched in both stellar mass and signal-to-noise.We also present clear evidence that satellite galaxies, as a population,exhibit more asymmetric HI spectra than centrals and that group centralgalaxies show a slightly higher rate of HI asymmetries compared to isolatedcentrals. All these results support a scenario in which environmentalprocesses, in particular those responsible for gas removal, are the dominantdriver of asymmetry in xGASS.

xGASS: Robust quantification of asymmetries in global HI spectra and their relationship to environmental processes