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

The highly r-process enhanced (r-II) metal-poor halo stars we observe todaycould play a key role in understanding early ultra-faint dwarf galaxies, thesmallest building blocks of the Milky Way. If a significant fraction ofmetal-poor r-II halo stars originated in the ultra-faint dwarf galaxies thatmerged to help form the Milky Way, observations of r-II stars could help usstudy these now-destroyed systems and probe the formation history of ourGalaxy. To conduct our initial investigation into this possible connection, weuse high-resolution cosmological simulations of Milky-Way-mass galaxies fromthe Caterpillar suite in combination with a simple, empirically motivatedtreatment of r-process enrichment. We determine the fraction of metal-poor halostars that could have formed from highly r-process enhanced gas innow-destroyed low-mass ultra-faint dwarf galaxies, the simulated r-II fraction,and compare it to the "as observed" r-II fraction. We find that the simulatedfraction, f_{r-II,sim} ~ 1-2%, can account for around half of the "as observed"fraction, f_{r-II,obs} ~ 2-4%. The "as observed" fraction likely overrepresentsthe fraction of r-II stars due to incomplete sampling, though, meaningf_{r-II,sim} likely accounts for more than half of the true f_{r-II,obs}.Further considering some parameter variations and scatter between individualsimulations, the simulated fraction can account for around 20-80% of the "asobserved" fraction.

The Origin of r-process Enhanced Metal-Poor Halo Stars In Now-Destroyed Ultra-Faint Dwarf Galaxies