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Related papers: Dynamical models for the Sculptor dwarf spheroidal…

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Aims: We aim to compute the binary fraction of "classical" dwarf spheroidal galaxies (dSphs) that are satellites of the Milky Way (MW). This value can offer insights into the binary fraction in environments that are less dense and more…

In previous work we have presented Schwarzschild models of the Sculptor dSph, demonstrating that this system could be embedded in dark matter halos that are either cusped or cored. Here we show that the non-parametric distribution function…

Astrophysics of Galaxies · Physics 2015-06-19 Maarten A. Breddels , Amina Helmi

We have found evidence for the presence of two distinct ancient stellar components (both geq 10 Gyr old) in the Sculptor dwarf spheroidal galaxy. We used the ESO Wide Field Imager (WFI) in conjunction with the VLT/FLAMES spectrograph to…

This paper introduces a new two-parameter family of dwarf spheroidal (dSph) galaxy models. The density distribution has a Plummer profile and falls like the inverse fourth power of distance in projection, in agreement with the star-count…

Astrophysics · Physics 2009-11-07 M. I. Wilkinson , J. Kleyna , N. W. Evans , G. Gilmore

We present the high resolution spectroscopic study of five -3.9<=[Fe/H]<=-2.5 stars in the Local Group dwarf spheroidal, Sculptor, thereby doubling the number of stars with comparable observations in this metallicity range. We carry out a…

We use controlled $N$-body experiments to study the dynamical evolution of dwarf spheroidal galaxies (dSphs) embedded in dark-matter (DM) haloes containing a large population of dark subhaloes. We show that stellar orbits subject to…

Astrophysics of Galaxies · Physics 2026-04-28 Jorge Peñarrubia , Ethan O. Nadler

We present BV photometry of the Sculptor dwarf galaxy to V=22. These data give evidence for a bimodality in Sculptor's metallicity distribution based on a discontinuity in the luminosities of horizontal branch (HB) stars and by the presence…

Astrophysics · Physics 2009-10-31 S. R. Majewski , M. H. Siegel , Richard J. Patterson , R. T. Rood

We have used high-resolution, high signal-to-noise spectra obtained with the VLT and UVES to determine abundances of 17 elements in 4 red giants in the Sculptor dwarf spheroidal galaxy. Our [Fe/H] values range from --2.10 to --0.97,…

We investigate whether the subhalos of Lambda-CDM galaxy halos have potentials consistent with the observed properties of Milky Way satellites, particularly those with high-quality photometric and kinematic data: Fornax, Leo I, Sculptor,…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 Louis E. Strigari , Carlos S. Frenk , Simon D. M. White

Five nearby dwarf irregular galaxies, amongst the recently surveyed dwarf members of the Sculptor and Centaurus A groups (at 2.5 Mpc and 3.5 Mpc), have been imaged in neutral hydrogen (HI) with the Australia Telescope and the Very Large…

Astrophysics · Physics 2007-05-23 Stephanie Cote , Ken Freeman , Claude Carignan

We study the chemical and kinematic properties of the first galaxies which formed at a high redshift, using high resolution cosmological numerical simulations, and compared them with the recent observational results for the Sculptor dwarf…

Astrophysics · Physics 2009-11-13 Daisuke Kawata , Nobuo Arimoto , Renyue Cen , Brad K. Gibson

Dwarf spheroidal (dSph) galaxies are considered the basic building blocks of the galaxy formation process in the LCDM (Lambda Cold Dark Matter) hierarchical cosmological model. These galaxies are believed to be the most dark matter (DM)…

Astrophysics of Galaxies · Physics 2015-06-16 P. Assmann , M. Fellhauer , M. I. Wilkinson , R. Smith , M. Blaña

The morphological properties of the Carina, Sculptor and Fornax dwarfs are investigated using new wide field data with a total area of 29 square degrees. The stellar density maps are derived, hinting that Sculptor possesses tidal tails…

Astrophysics · Physics 2009-11-07 C. J. Walcher , J. W. Fried , A. Burkert , R. S. Klessen

We present stellar radial velocity data for the Draco dwarf spheroidal galaxy obtained using the AF2/WYFFOS instrument combination on the William Herschel Telescope. Our dataset consists of 186 member stars, 159 of which have good quality…

Astrophysics · Physics 2009-11-07 J. T. Kleyna , M. I. Wilkinson , N. W. Evans , G. Gilmore

We use orbit based dynamical models to fit the 2nd and 4th moments of the line of sight velocity distributions of the Fornax, Sculptor, Carina and Sextans dwarf spheroidal galaxies. Our goal is to compare dark matter profile models of these…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-15 M. A. Breddels , A. Helmi

We present [C/Fe] and [N/Fe] abundance ratios and CH({\lambda}4300) and S({\lambda}3883) index measurements for 94 red giant branch (RGB) stars in the Sculptor dwarf spheroidal galaxy from VLT/VIMOS MOS observations at a resolving power R=…

Astrophysics of Galaxies · Physics 2016-01-06 C. Lardo , G. Battaglia , E. Pancino , D. Romano , T. J. L. de Boer , E. Starkenburg , E. Tolstoy , M. J. Irwin , P. Jablonka , M. Tosi

We present a new determination of the mass content of the Sculptor dwarf spheroidal galaxy, based on a novel approach which takes into account the two distinct stellar populations present in this galaxy. This method helps to partially break…

Astrophysics · Physics 2015-05-13 G. Battaglia , A. Helmi , E. Tolstoy , M. Irwin

The hierarchical clustering inherent in Lambda-CDM cosmology seems to produce many of the observed characteristics of large-scale structure. But some glaring problems still remain, including the over-prediction (by a factor 10) of the…

Astrophysics · Physics 2016-02-03 Majd Abdelqader , Fulvio Melia

We present projected velocity dispersion profiles for the Draco and Ursa Minor (UMi) dwarf spheroidal galaxies based on 207 and 162 discrete stellar velocities, respectively. Both profiles show a sharp decline in the velocity dispersion…

Astrophysics · Physics 2009-11-10 M. I. Wilkinson , J. T. Kleyna , N. W. Evans , G. F. Gilmore , M. J. Irwin , E. K. Grebel

We use numerical simulations to study a formation scenario for dwarf spheroidal galaxies in which their stellar populations are the products of the dissolution of open star clusters and stellar associations within cosmological dark matter…

Astrophysics of Galaxies · Physics 2015-06-15 Paulina Assmann , Michael Fellhauer , Mark I. Wilkinson , Rory Smith