English
Related papers

Related papers: Chemodynamically Characterizing the Jhelum Stellar…

200 papers

We present high-resolution Magellan/MIKE spectroscopy of 42 red giant stars in seven stellar streams confirmed by the Southern Stellar Stream Spectroscopic Survey (S5): ATLAS, Aliqa Uma, Chenab, Elqui, Indus, Jhelum, and Phoenix. Abundances…

We report evidence from APOGEE for the presence of a new metal-poor stellar structure located within $\sim$4~kpc of the Galactic centre. Characterised by a chemical composition resembling those of low mass satellites of the Milky Way, this…

In this work, we present high-resolution spectroscopic observations for six metal-poor stars with [Fe/H]<-3 (including one with [Fe/H]<-4), selected using narrow-band Ca II HK photometry from the DECam MAGIC Survey. The spectroscopic data…

The Milky Way halo was predominantly formed by the merging of numerous progenitor galaxies. However, our knowledge of this process is still incomplete, especially in regard to the total number of mergers, their global dynamical properties…

Based on high-quality APOGEE DR17 and Gaia DR3 data for 1,742 red giants stars within 5 kpc of the Sun and not rotating with the Galactic disc ($V_\phi <$ 100 km s$^{-1}$), we use the nonlinear technique of unsupervised analysis t-SNE to…

We present a view of the stellar halo in the inner-central regions of the Milky Way (R <~ 10 kpc) mapped by RR Lyrae stars. The combined BRAVA-RR/APOGEE RR Lyrae catalog is used to obtain a sample of 281 RR Lyrae stars located in the bulge…

The stellar mass in the halo of the Milky Way is notoriously difficult to determine, owing to the paucity of its stars in the solar neighbourhood. With tentative evidence from $\it{Gaia}$ that the nearby stellar halo is dominated by a…

Astrophysics of Galaxies · Physics 2020-01-29 J. Ted Mackereth , Jo Bovy

We present new identifications of five red giant stars in the Galactic halo with chemical abundance patterns that indicate they originally formed in globular clusters. Using data from the Apache Point Observatory Galactic Evolution…

Based on the updated M giant star catalog selected from LAMOST DR9, we iden-tify substructures within the integrals-of-motion space through Friends-of-Friends cluster-ing algorithm. We obtain members belonging to several known…

Astrophysics of Galaxies · Physics 2025-09-10 Longfei Ding , Jing Li , Xiang-Xiang Xue , Hao Tian , Zhengzhou Yan , Gang Zhao

We report the serendipitous discovery of a nitrogen-rich, mildly metal-poor ([Fe/H]=-1.08) giant star in a single-lined spectroscopic binary system found in the SDSS-IV Apache Point Observatory Galactic Evolution Experiment (APOGEE-2)…

The majority of the Milky Way's stellar halo consists of debris from our Galaxy's last major merger, the Gaia-Sausage-Enceladus (GSE). In the past few years, stars from GSE have been kinematically and chemically studied in the inner $30$…

Observations of the Milky Way's stellar halo find that it is predominantly comprised of a radially biased population of stars, dubbed the Gaia Sausage--Enceladus, or GSE. These stars are thought to be debris from dwarf galaxy accretion…

Astrophysics of Galaxies · Physics 2026-04-08 Dylan Folsom , Mariangela Lisanti , Lina Necib , Danny Horta , Mark Vogelsberger , Lars Hernquist

By performing an orbital analysis within a Galactic model including a bar, we found that it is plausible that the newly discovered stars that show enhanced Al and N accompanied by Mg underabundances may have formed in the outer halo, or…

Astrophysics of Galaxies · Physics 2017-10-23 J. G. Fernández-Trincado , D. Geisler , E. Moreno , O. Zamora , A. C. Robin , S. Villanova

We report the results of an unsupervised decomposition of the local stellar halo in the chemo-dynamical space spanned by the abundance measurements from APOGEE DR17 and GALAH DR3. In our Gaussian Mixture Model, only four independent…

Astrophysics of Galaxies · Physics 2023-01-31 G. C. Myeong , Vasily Belokurov , David S. Aguado , N. Wyn Evans , Nelson Caldwell , James Bradley

We investigate the properties of mergers comparable to the Gaia-Sausage-Enceladus (GSE) using cosmological hydrodynamical simulations of Milky Way-like galaxies. The merger progenitors span an order of magnitude in their peak stellar mass…

The globular cluster Palomar 5 (Pal 5) is in the process of being tidally shredded as it orbits the Milky Way. Its core is currently at a heliocentric distance of ~21 kpc, near apogalacticon (~18 kpc), and it reaches ~5-7 kpc at…

The accretion of Gaia-Enceladus/Sausage (GES) onto the Milky Way (MW) is one of the most prominent features of the Galactic halo revealed by the combination of the Gaia satellite and large spectroscopic surveys. This massive accretion…

Astrophysics of Galaxies · Physics 2026-02-03 L. Berni , M. Palla , L. Magrini , L. Spina

Since the advent of $Gaia$ astrometry, it is possible to identify massive accreted systems within the Galaxy through their unique dynamical signatures. One such system, $Gaia$-Sausage-Enceladus (GSE), appears to be an early "building block"…

We identify stellar tidal debris from the $\omega$ Centauri ($\omega$ Cen) system among field stars in the APOGEE survey via chemical tagging using a neural network trained on APOGEE observations of the $\omega$ Cen core. We find a total of…