scholarly journals Kinematics of Metal-poor Stars in the Galaxy. III. Formation of the Stellar Halo and Thick Disk as Revealed from a Large Sample of Nonkinematically Selected Stars

2000 ◽  
Vol 119 (6) ◽  
pp. 2843-2865 ◽  
Author(s):  
Masashi Chiba ◽  
Timothy C. Beers
Keyword(s):  
Thick Disk ◽  
Large Sample ◽  
The Galaxy ◽  
Stellar Halo

scholarly journals Evolution of the Galactic Halo and Disk

1995 ◽  
Vol 164 ◽  
pp. 99-107
Author(s):  
Gerard Gilmore
Keyword(s):  
Angular Momentum ◽  
Galactic Halo ◽  
Evolutionary Model ◽  
Thick Disk ◽  
Structural Components ◽  
Stellar Kinematics ◽  
Chemical Abundances ◽  
The Galaxy ◽  
Stellar Halo ◽  
Discrete Populations

Correlations between stellar kinematics and chemical abundances are fossil evidence for evolutionary connections between Galactic structural components. Extensive stellar surveys show that the only tolerably clear distinction between galactic components appears in the distributions of specific angular momentum. Here the stellar metal-poor halo and the metal-rich bulge are indistinguishable from each other, as are the thick disk and the old disk. Each pair is very distinct from the other. This leads to an evolutionary model in which the metal-poor stellar halo evolves into the inner bulge, while the thick disk is a precursor to the thin disk. These evolutionary sequences are distinct. The galaxy is made of two discrete “populations”, one of low and one of high angular momentum. Some (minor?) complexity is added to this picture by the debris of late and continuing mergers, which will be especially important in the outer stellar halo.

scholarly journals Element Abundance Analysis of the Metal-rich Stellar Halo and High-velocity Thick Disk in the Galaxy

2021 ◽  
Vol 915 (1) ◽  
pp. 9
Author(s):  
Haifan Zhu ◽  
Cuihua Du ◽  
Yepeng Yan ◽  
Jianrong Shi ◽  
Jun Ma ◽  
...  
Keyword(s):  
High Velocity ◽  
Thick Disk ◽  
Element Abundance ◽  
The Galaxy ◽  
Stellar Halo

scholarly journals Existence of the Metal-rich Stellar Halo and High-velocity Thick Disk in the Galaxy

2020 ◽  
Vol 903 (2) ◽  
pp. 131
Author(s):  
Yepeng Yan ◽  
Cuihua Du ◽  
Hefan Li ◽  
Jianrong Shi ◽  
Jun Ma ◽  
...  
Keyword(s):  
High Velocity ◽  
Thick Disk ◽  
The Galaxy ◽  
Stellar Halo

scholarly journals The Age of Old Galactic Populations

1998 ◽  
Vol 11 (1) ◽  
pp. 560-561
Author(s):  
M. Grenon
Keyword(s):  
High Velocity ◽  
Radial Velocities ◽  
Thick Disk ◽  
Early Evolution ◽  
Galactic Bulge ◽  
Colour Class ◽  
The Galaxy ◽  
Nearby Stars

As a preparation to the HIPPARCOS mission, a large observing programme on NLTT stars (propermotion > 0.18 ″/yr) was started in Genevaphotometry. The original programme consists of 10047 stars brighter than mR = 11.5, or mR = 12.5 if of colour class m. Among them, 7813 targets could be included in the HIPPARCOS programme, selected according to their observability and internal priorities in favour of large parallaxe stars (photometric distances < 100 pc) and high-velocity stars. The bulk of new nearby, halo, mild-metal poor and SMR stars in the HIP Catalogue originates from this proposal (N° 139). No less than 208 new nearby stars with π ≥ 40 mas were discovered south of δ +10°, the closest has π(HIP)= 182 mas. Radial velocities were obtained with CORAVEL at OHP and ESO. Most aspects of the early evolution of the Galaxy may be addressed with this sample. Here we discuss, as examples, the ages of the thick disk and of the galactic bulge.

scholarly journals The merger that led to the formation of the Milky Way’s inner stellar halo and thick disk

Nature ◽  
2018 ◽  
Vol 563 (7729) ◽  
pp. 85-88 ◽  
Author(s):  
Amina Helmi ◽  
Carine Babusiaux ◽  
Helmer H. Koppelman ◽  
Davide Massari ◽  
Jovan Veljanoski ◽  
...  
Keyword(s):  
Thick Disk ◽  
Stellar Halo

scholarly journals The chemical fingerprints of the thin and the thick disk

2008 ◽  
Vol 4 (S254) ◽  
pp. 197-202
Author(s):  
Sofia Feltzing ◽  
Sally Oey ◽  
Thomas Bensby
Keyword(s):  
Past History ◽  
Thick Disk ◽  
Chemical Abundance ◽  
Dwarf Stars ◽  
Abundance Patterns ◽  
The Galaxy ◽  
Thin And Thick Disks ◽  
Thick Disks ◽  
Definition Of ◽  
Galactic Stellar Populations

AbstractThe past history and origin of the different Galactic stellar populations are manifested in their different chemical abundance patterns. We obtained new elemental abundances for 553 F and G dwarf stars, to more accurately quantify these patterns for the thin and thick disks. However, the exact definition of disk membership is not straightforward. Stars that have a high likelihood of belonging to the thin disk show different abundance patterns from those for the thick disk. In contrast, we show that stars for the Hercules Stream do not show unique abundance patterns, but rather follow those of the thin and thick disks. This strongly suggests that the Hercules Stream is a feature induced by internal dynamics within the Galaxy rather than the remnant of an accreted satellite.

scholarly journals THE THICK DISK IN THE GALAXY NGC 4244 FROM S4G IMAGING

2011 ◽  
Vol 729 (1) ◽  
pp. 18 ◽  
Author(s):  
Sébastien Comerón ◽  
Johan H. Knapen ◽  
Kartik Sheth ◽  
Michael W. Regan ◽  
Joannah L. Hinz ◽  
...  
Keyword(s):  
Thick Disk ◽  
The Galaxy
Sign in / Sign up

Export Citation Format

Share Document