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Related papers: Sgr dSph: a bridge between Dwarf Galaxies and DLAs…

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We present iron and $\alpha$ element (Mg, Ca, Ti) abundances for a sample of 15 Red Giant Branch stars belonging to the main body of the Sagittarius dwarf Spheroidal galaxy. Abundances have been obtained from spectra collected using the…

Astrophysics · Physics 2016-08-30 L. Monaco , M. Bellazzini , P. Bonifacio , F. R. Ferraro , G. Marconi , E. Pancino , L. Sbordone , S. Zaggia

We present deep CCD photometry of a field in the newly discovered dwarf spheroidal galaxy in Sagittarius (hereafter Sgr), and of a nearby control field. These data (totaling ~3.5 hrs exposure time in V and I) were used to produce…

Astrophysics · Physics 2009-10-22 Mario Mateo , A. Udalski , M. Szymanski , J. Kaluzny , M. Kubiak , W. Krzeminski

We present metallicity and radial velocity for 450 bonafide members of the Sagittarius dwarf spheroidal (Sgr dSph) galaxy, measured from high resolution (R~18000) FLAMES@VLT spectra. The targets were carefully selected (a) to sample the…

We use time-resolved spectra from the Apache Point Observatory Galactic Evolution Experiment (APOGEE) to examine the distribution of radial velocity (RV) variations in 249 stars identified as members of the Sagittarius (Sgr) dwarf…

The main characteristics of a wide photometric survey of the Sgr dwarf spheroidal galaxy are shortly presented. V and I photometry has been obtained for ~ 90000 stars toward Sgr and for ~ 9000 stars in a region devoid of Sgr stars (for…

Astrophysics · Physics 2007-05-23 M. Bellazzini , F. R. Ferraro , R. Buonanno

The Keck I telescope has been used to obtain HIRES spectra for red giants belonging to the Draco, Sextans and Ursa Minor dwarf spheroidal (dSph) galaxies. An analysis of these spectra is presented, along with abundance ratios for more than…

Astrophysics · Physics 2011-08-23 Matthew Shetrone , Patrick Cote , W. L. W. Sargent

Dwarf galaxies like Sagittarius (Sgr) provide a unique window into the early stages of galactic chemical evolution, particularly through their metal-poor stars. By studying the chemical abundances of stars in the Sgr core and tidal streams,…

Astrophysics of Galaxies · Physics 2025-01-27 Xiaowei Ou , Alexander Yelland , Anirudh Chiti , Anna Frebel , Guilherme Limberg , Mohammad K. Mardini

We predict the metallicity distribution of stars and the age-metallicity relation for 6 Dwarf Spheroidal (dSph) galaxies of the Local Group by means of a chemical evolution model which is able to reproduce several observed abundance ratios…

Astrophysics · Physics 2009-11-10 Gustavo A. Lanfranchi , Francesca Matteucci

Hypervelocity stars (HVSs) are valuable tracers of extreme dynamical processes. The Sagittarius dwarf spheroidal galaxy (Sgr dSph), currently undergoing tidal disruption, offers a unique environment to search for such stars. We aim to…

Astrophysics of Galaxies · Physics 2026-03-17 Jian Zhang , Cuihua Du , Mingji Deng , Haoyang Liu , Zhongcheng Li

Numerical models of the tidal disruption of the Sagittarius (Sgr) dwarf galaxy have recently been developed that for the first time simultaneously satisfy most observational constraints on the angular position, distance, and radial velocity…

Astrophysics of Galaxies · Physics 2015-05-19 David R. Law , Steven R. Majewski

The Sagittarius galaxy (Sgr), the closest satellite galaxy of the Milky Way, has survived for many orbits about the Galaxy. Extant numerical calculations modeled this galaxy as a system with a centrally-concentrated mass profile, following…

Astrophysics · Physics 2008-11-26 Rodrigo Ibata , Rosemary Wyse , Gerard Gilmore , Michael Irwin , Nicholas Suntzeff

We present a large sample of fully self-consistent hydrodynamical Nbody/Tree-SPH simulations of isolated dwarf spheroidal galaxies (dSphs). It has enabled us to identify the key physical parameters and mechanisms at the origin of the…

Astrophysics of Galaxies · Physics 2015-05-13 Y. Revaz , P. Jablonka , T. Sawala , V. Hill , B. Letarte , M. Irwin , G. Battaglia , A. Helmi , M. D. Shetrone , E. Tolstoy , K. A. Venn

Studies of the early chemical evolution of some larger dwarf galaxies ( $>10^7$ solar masses) are limited by the small number of stars known at low metallicities in these systems. Here we present metallicities and carbon abundances for…

Astrophysics of Galaxies · Physics 2020-10-14 Anirudh Chiti , Kylie Y. Hansen , Anna Frebel

The Sagittarius dwarf Spheroidal galaxy is the nearest neighbor of the Milky Way. Moving along a short period quasi-polar orbit within the Halo, it is being destroyed by the tidal interaction with our Galaxy, losing its stellar content…

Astrophysics · Physics 2009-11-11 L. Sbordone , P. Bonifacio , R. Buonanno , G. Marconi , L. Monaco , S. Zaggia

We demonstrate that there is a clear statistical correlation between the (X,Y,Z,V_r) phase-space distribution of the outer halo Galactic globular clusters (having 10 kpc <= R_GC <= 40 kpc) and the orbital path of the Sagittarius dwarf…

Astrophysics · Physics 2009-11-07 Michele Bellazzini , Francesco R. Ferraro , Rodrigo Ibata

We present an abundance analysis based on high resolution spectra of 10 stars selected to span the full range in metallicity in the Ursa Minor dwarf spheroidal galaxy. We find [Fe/H] for the sample stars ranges from -1.35 to -3.10 dex and…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 Judith G. Cohen , Wenjin Huang

Photometry of a large field around the young globular cluster Palomar 12 has revealed the main-sequence of a low surface-brightness stellar system. This main-sequence is indicative of a stellar population that varies significantly in…

Astrophysics · Physics 2009-11-07 D. Martinez-Delgado , R. Zinn , R. Carrera , C. Gallart

This paper reviews recent abundance results of local dSph giants. All dSph systems seem to show evidence of slow star formation rates, compared to the Milky Way, based on the most metal-rich stars exhibiting low [even-Z/Fe] ratios and high…

Astrophysics · Physics 2007-05-23 Matthew Shetrone

We present abundances of C, O, Ti, and Fe for eleven M-giant stars in the trailing tidal arm of the Sagittarius dwarf (Sgr). The abundances were derived by comparing synthetic spectra with high-resolution infrared spectra obtained with the…

Astrophysics of Galaxies · Physics 2015-05-19 Stefan C. Keller , David Yong , Gary S. Da Costa

Context. The Sagittarius (Sgr) dwarf spheroidal galaxy is currently being disrupted under the strain of the Milky Way. A reliable reconstruction of Sgr star formation history can only be obtained by combining core and stream information.…

Astrophysics · Physics 2009-11-11 L. Monaco , M. Bellazzini , P. Bonifacio , A. Buzzoni , F. R. Ferraro , G. Marconi , L. Sbordone , S. Zaggia