Results 51 to 60 of about 29,619 (304)

Reliability of the Measured Velocity Anisotropy of the Milky Way Stellar Halo [PDF]

The Astrophysical Journal, 2017
Abstract Determining the velocity distribution of halo stars is essential for estimating the mass of the Milky Way and for inferring its formation history. Since the stellar halo is a dynamically hot system, the velocity distribution of halo stars is well described by the three-dimensional velocity dispersions
Kohei Hattori, Monica Valluri, Sarah R. Loebman, Eric F. Bell   +3 more
openaire   +4 more sources

The R-Process Alliance: Chemodynamically Tagged Groups. II. An Extended Sample of Halo r-process-enhanced Stars

The Astrophysical Journal, 2023
Orbital characteristics based on Gaia Early Data Release 3 astrometric parameters are analyzed for ∼1700 r -process-enhanced (RPE; [Eu/Fe] > +0.3) metal-poor stars ([Fe/H] ≤ −0.8) compiled from the R -Process Alliance, the GALactic Archaeology with ...
Derek Shank, Timothy C. Beers, Vinicius M. Placco, Dmitrii Gudin, Thomas Catapano, Erika M. Holmbeck, Rana Ezzeddine, Ian U. Roederer, Charli M. Sakari, Anna Frebel, Terese T. Hansen   +10 more
doaj   +1 more source

Insight Into the Formation of the Milky Way Through Cold Halo Substructure. I. The ECHOS of Milky Way Formation [PDF]

, 2009
We identify ten -- seven for the first time -- elements of cold halo substructure (ECHOS) in the volume within 17.5 kpc of the Sun in the inner halo of the Milky Way.
Abadi, Abadi, Abazajian, Allende Prieto, Allende Prieto, An, Audrey Simmons, Bell, Belokurov, Belokurov, Binney, Bovy, Brian Yanny, Bullock, Carlos Allende Prieto, Carretta, Chen, Chiba, Chiba, Clem, Constance M. Rockosi, Dan Oravetz, Diemand, Dmitry Bizyaev, Duffau, Elena Malanushenko, Fellhauer, Font, Gilmore, Gilmore, Gould, Grillmair, Grillmair, Grillmair, Grillmair, Gunn, Gunn, Harding, Helmi, Helmi, Hogg, Howard, Howard Brewington, Ibata, Ivezić, Ivezić, Johnston, Johnston, Johnston, Jurić, Kaike Pan, Kepley, Kevin C. Schlaufman, Kirby, Klement, Klement, Law, Lee, Lee, Lindegren, Majewski, Martínez-Delgado, Monet, Morrison, Morrison, Munn, Newberg, Nissen, Odenkirchen, Padmanabhan, Peñarrubia, Pier, Robertson, Rocha-Pinto, Rockosi, Sirko, Sirko, Smith, Smith, Sommer-Larsen, Starkenburg, Steinmetz, Stephanie Snedden, Stewart, Timothy C. Beers, Viktor Malanushenko, Vivas, Vivas, Watkins, White, Willett, Xue, Yanny, Yanny, Yanny, York, Young Sun Lee, Zolotov, Zwitter   +98 more
core   +2 more sources

The stellar halo in the inner Milky Way: predicted shape and kinematics [PDF]

Monthly Notices of the Royal Astronomical Society: Letters, 2016
Abstract We have used N-body simulations for the Milky Way to investigate the kinematic and structural properties of the old metal-poor stellar halo in the barred inner region of the Galaxy. We find that the extrapolation of the density distribution for bulge RR Lyrae stars, ρ ∼ r−3, approximately matches the number density of RR Lyrae ...
Matthieu Portail, Angeles Pérez-Villegas, Ortwin Gerhard   +2 more
openaire   +3 more sources

The velocity dispersion and mass profile of the Milky Way [PDF]

, 2006
We re-analyse the velocity-dispersion profile sigma(r) at radii r>10 kpc in the Galactic stellar halo, recently derived by Battaglia et al. (2005), who concluded that, for constant velocity anisotropy of the tracers, these data rule out a flat circular ...
Battaglia, Bullock, Chiba, Côté, Côté, Dean E. McLaughlin, Dehnen, Dehnen, Dekel, Gould, Harris, Harris, Jalpesh Sachania, Kochanek, Mamon, Morrison, Méndez, Navarro, Navarro, Richtler, Rohlfs, Romanowsky, Walter Dehnen, Yanny   +23 more
core   +2 more sources

Cosmological insights into the assembly of the radial and compact stellar halo of the Milky Way [PDF]

Monthly Notices of the Royal Astronomical Society, 2020
ABSTRACT Recent studies using Gaia DR2 have identified a massive merger in the early history of the Milky Way (MW) whose debris is dominated by radial and counterrotating orbits. This event, dubbed the Gaia-Enceladus/Gaia-Sausage (GE/GS), is also hypothesized to have built the majority of the inner stellar halo.
Lars Hernquist, Amina Helmi, Laura V Sales, Lydia M Elias   +3 more
openaire   +4 more sources

Assembly of the outer Galactic stellar halo in the hierarchical model

, 2010
We provide a set of numerical N-body simulations for studying the formation of the outer Milky Ways's stellar halo through accretion events. After simulating minor mergers of prograde and retrograde orbiting satellite halo with a Dark Matter main halo ...
Adelman-McCarthy, Belokurov, Binney, Boylan-Kolchin, Bullock, Chiba, Curir, Grillmair, Huang, Miceli, Moore, Navarro, Press, White, Yanny, Zolotov   +15 more
core   +1 more source

The Dichotomy of the Halo of the Milky Way

, 2008
We summarize evidence that the halo of the Milky Way comprises two different, and broadly overlapping, stellar components. The two structures exhibit different chemical compositions, spatial distributions, and kinematics.
Akira Ohnishi, Daniela Carollo, Kiyoshi Kato, Masayuki Y. Fujimoto, Shigeru Kubono, Takaya Nozawa, Takuma Suda, Timothy C. Beers, Toshitaka Kajino   +8 more
core   +1 more source

The stability of stellar discs in Milky Way-sized dark matter haloes [PDF]

Monthly Notices of the Royal Astronomical Society, 2015
22 pages, 23 figures, 1 tables. Accepted for publication in MNRAS.
Volker Springel, Volker Springel, Denis Yurin, Denis Yurin   +3 more
openaire   +3 more sources

Are dSph galaxies Galactic building blocks?

EPJ Web of Conferences, 2012
Dwarf spheroidal galaxies (dSph) are frequently assumed to represent surviving examples of a vast now destroyed population of small systems in which many of the stars now forming the Milky Way were formed. Ongoing accretion and considerable sub-structure
Gilmore G., Asiri H.M.
doaj   +1 more source