相关论文: The Arcturus Moving Group: Its Place in the Galaxy

The Arcturus stream is an over-density of stars in velocity space and its origin has been much debated recently without any clear conclusion. Resolving the nature of the Arcturus stream can provide clues to the formation history of the…

We reanalyze the group of stars associated kinematically with Arcturus (Eggen 1971), and confirm that they constitute a peculiar grouping of metal-poor stars with similar apocentric radius, common angular momentum, and distinct metal…

Thick discs are nearly ubiquitous components of the discs of present-day galaxies. It has been proposed that a fraction of their stars has been accreted. Here, we aim to find whether accretion of satellites is the main thick disc formation…

The study of the Milky Way stellar discs in the context of galaxy formation is discussed. In particular we explore the properties of the Milky Way disc using a new sample of about 550 dwarf stars for which we have recently obtained…

We present a detailed analysis of high-resolution, high S/N spectra for 5 Aquarius stream stars observed with the MIKE spectrograph on the Magellan Clay telescope. Our sample represents one third of the 15 known members in the stream. We…

Recent dynamical analysis based on Gaia data have revealed major accretion events in Milky Way's history. Nevertheless, our understanding of the primordial Galaxy is hindered because the bona fide identification of the most metal-poor and…

Studies of the kinematics and chemical compositions of Galactic globular clusters (GCs) enable the reconstruction of the history of star formation, chemical evolution, and mass assembly of the Galaxy. Using the latest data release (DR16) of…

We adopt a scenario in which the Galactic thick disk was formed by minor merging between the first generation of the Galactic thin disk (FGTD) and a dwarf galaxy about 9 Gyr ago and thereby investigate chemical and dynamical properties of…

Sulfur is a volatile chemical element that plays an important role in tracing the chemical evolution of galaxies. However, its nucleosynthesis origin and abundance variations are still unclear. The goal of the present article is to…

Studies of elemental abundances in stars belonging to the thin and the thick disk of our Galaxy are reviewed. Edvardsson et al. (1993) found strong evidence of [alpha/Fe] variations among F and G main sequence stars with the same [Fe/H] and…

From correlations between orbital parameters, several new coherent groups of stars were recently identified in the Galactic disc and suggested to correspond to remnants of disrupted satellites. To reconstruct their origin at least three…

The existence of old dispersed stellar groups within the Milky Way disk is still controversial. Are they the debris of ancient star-forming aggregates, or short-lived artifacts of dynamical origin? With detailed elemental abundance…

Our Galaxy is a complex machine in which several processes operate simultaneously: metal-poor gas is accreted, is chemically enriched by dying stars, and then drifts inwards, surrendering its angular momentum to stars; new stars are formed…

We examine the chemical and dynamical structure in the solar neighbourhood of a model Galaxy that is the endpoint of a simulation of the chemical evolution of the Milky Way in the presence of radial mixing of stars and gas. Although the…

The search for accreted satellites in the Galactic disk is a challenging task, to which Gaia plays a crucial role in synergy with ground-based spectroscopic surveys. In 2021, Re Fiorentin et al. discovered five substructures with disk…

We analyse the phase-space structure of simulated thick discs that are the result of a significant merger between a disc galaxy and a satellite. Our main goal is to establish what would be the characteristic imprints of a merger origin for…

Using modern published data on velocities and spectroscopic definitions of chemical elements in stellar objects of the Galaxy, we investigated the relationship of chemical composition with the kinematics of different populations. The paper…

We present abundances for 20 elements for stars in two stellar streams identified by Arifyanto & Fuchs (2006, A&A, 449, 533): 18 stars from the Arcturus stream and 26 from a new stream, which we call AF06 stream, both from the Galactic…

We search for the existence of chemically-distinct stellar components in the solar neighbourhood using published data. Extending earlier work, we show that when the abundances of Fe, alpha elements, and the r-process element Eu are…

The Galactic bulge, that is the prominent out-of-plane over-density present in the inner few kiloparsecs of the Galaxy, is a complex structure, as the morphology, kinematics, chemistry and ages of its stars indicate. To understand the…