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

Systems of shells and polar rings in early-type galaxies are considered "bonafide" tracers of mass accretion and/or mergers. Their high frequency in lowdensity environments suggests that such episodes could drive the evolution ofat least a fraction of the early-type galaxy population. Their UV emission iscrucial to test whether these galaxies host ongoing/recent star formation. Weused far and near ultraviolet, optical, near infrared images, HI maps, and linestrength indices to investigate the nuclear and outer regions of the galaxiesas well as the regions where fine structures are present. The GALEX Near (NUV)and Far UV (FUV) images of MCG-05-07-001 and NGC 1210 show complex tidal tailsand debris structures. The UV morphology of both galaxies appears so differentfrom the optical one that the early-type classification may not apply. In bothGALEX bands the polar ring of MCG-05-07-001 is the dominant feature, whereas anextended tidal tail dominates the FUV bands of NGC 1210. In MCG-05-07-001 andNGC 1210 there is a strong correlation between structures detected in the FUVand NUV bands and in HI. NGC 5329 does not show evidence of shells in the UV.We try to constrain the age of the accretion episode or merger which gave riseto the shells and polar rings with the aid of composite stellar populationsthat take the presence of dust into account. The presence of HI in bothMCG-05-07-001 and NGC 1210 argues in favour of wet mergers. Models suggest thepresence of very young stellar populations in MCG-05-07-001: the observationscould be explained in the framework of a conspicuous burst of star formationthat occurred <=1 Gyr ago and involved a large fraction of the galaxy mass. Ourmodels suggest that also the nuclei of NGC 1210 and NGC 5329 could have beenrejuvenated by an accretion episode about 2-4 Gyr ago. (abridged)

GALEX UV properties of the polar ring galaxy MCG-05-07-001 and the shell galaxies NGC 1210 and NGC 5329