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

Observational studies of halo stars during the last two decades have placedsome limits on the quantity and nature of accreted dwarf galaxy contributionsto the Milky Way stellar halo by typically utilizing stellar phase-spaceinformation to identify the most recent halo accretion events. In this study wetested the prospects of using 2-D chemical abundance ratio distributions(CARDs) found in stars of the stellar halo to determine its formation history.First, we used simulated data from eleven "MW-like" halos to generate satellitetemplate sets of 2-D CARDs of accreted dwarf satellites which are comprised ofaccreted dwarfs from various mass regimes and epochs of accretion. Next, werandomly drew samples of $\sim10^{3-4}$ mock observations of stellar chemicalabundance ratios ([$\alpha$/Fe], [Fe/H]) from those eleven halos to generatesamples of the underlying densities for our CARDs to be compared to ourtemplates in our analysis. Finally, we used the expectation-maximizationalgorithm to derive accretion histories in relation to the satellite templateset (STS) used and the sample size. For certain STS used we typically canidentify the relative mass contributions of all accreted satellites to within afactor of 2. We also find that this method is particularly sensitive to olderaccretion events involving low-luminous dwarfs e.g. ultra-faint dwarfs -precisely those events that are too ancient to be seen by phase-space studiesof stars and too faint to be seen by high-z studies of the early Universe.Since our results only exploit two chemical dimensions and near-future surveyspromise to provide $\sim6-9$ dimensions, we conclude that these newhigh-resolution spectroscopic surveys of the stellar halo will allow us torecover its accretion history - and the luminosity function of infalling dwarfgalaxies - across cosmic time.

Reconstructing the Accretion History of the Galactic Stellar Halo from Chemical Abundance Ratio Distributions