The Gaia Sausage (GS) and the Sequoia represent major accretion events that formed stellar halo of Milky Way. A detailed chemical study these main building blocks provides a pristine view early steps Galaxy's assembly. We present results analysis UVES high-resolution spectroscopic observations at 8.2m VLT 9 Sausage/Sequoia members selected kinematically using DR2. season this set measurements w...

Abstract Despite recent progress, the astrophysical channels responsible for rapid neutron capture ( r -process) nucleosynthesis remain an unsettled question. Observations of kilonova following gravitational-wave-detected star merger GW170817 established mergers as one site -process, but additional sources may be needed to fully explain -process enrichment in universe. One intriguing possibilit...

We study the production of barium (Ba) and strontium (Sr) in ultrafaint dwarf galaxies (UFDs). Both r- s- processes produce these elements, one can infer contribution r-process from characteristic abundance pattern, whereas s-process remains largely unknown. show that current yield asymptotic giant branch (AGB) stars is not sufficient to explain Ba Sr abundances observed UFDs. Production elemen...

This research addresses the task of ontology enrichment by exploiting the large amount of structured information available in semantic wikis. The proposed solution makes use of ontological design patterns to guide the semiautomatic enrichment process and regular expressions or predefined values in the automatic enrichment process.