# Quantifying the (X/peanut)-shaped structure of the Milky Way – new constraints on the bar geometry

@article{Ciambur2017QuantifyingT,
title={Quantifying the (X/peanut)-shaped structure of the Milky Way – new constraints on the bar geometry},
author={Bogdan C. Ciambur and Alister W. Graham and Joss Bland-Hawthorn},
journal={Monthly Notices of the Royal Astronomical Society},
year={2017},
volume={471},
pages={3988-4004}
}
• Published 2017
• Physics
• Monthly Notices of the Royal Astronomical Society
The nature, size and orientation of the dominant structural components in the Milky Way's inner ~4 kpc - specifically the bulge and bar - have been the subject of conflicting interpretations in the literature. We present a different approach to inferring the properties of the long bar which extends beyond the inner bulge, via the information encoded in the Galaxy's X/peanut (X/P)-shaped structure. We perform a quantitative analysis of the X/P feature seen in WISE wide-field imaging at 3.4 $\mu… Expand #### Figures and Tables from this paper The structure of the Milky Way based on unWISE 3.4 μm integrated photometry • Physics • Monthly Notices of the Royal Astronomical Society • 2021 We present a detailed analysis of the Galaxy structure using an unWISE wide-field image at$3.4\,\mu$m. We perform a 3D photometric decomposition of the Milky Way taking into account (i) theExpand Edge-on boxes with X-features as parts of galactic bars • Physics • 2021 Context. This paper is a contribution to the discussion about whether the X/peanut component is part of the bar, or the bar itself. Aims. Our goal is to present a clear-cut case of a barred-spiralExpand Disk origin of the Milky Way bulge: the necessity of the thick disk In the Milky Way bulge, metal-rich stars form a strong bar and are more peanut-shaped than metal-poor stars. It has recently been claimed that this behavior is driven by the initial (i.e., before barExpand Evolution, Structure and Rotation of the Milky Way Galaxy Here we described the evolution and we determined the structure and rotation of the Milky Way. Our model is based on the Scale-Symmetric Theory (SST). We compared the theoretical results withExpand Anatomy of a buckling galactic bar Using N-body simulations we study the buckling instability in a galactic bar forming in a Milky Way-like galaxy. The galaxy is initially composed of an axisymmetric, exponential stellar disk embeddedExpand HERBS I: Metallicity and alpha enhancement along the Galactic bulge minor axis • Physics • Monthly Notices of the Royal Astronomical Society • 2019 To better understand the origin and evolution of the Milky Way bulge, we have conducted a survey of bulge red giant branch and clump stars using the High Efficiency and Resolution Multi-ElementExpand Modelling the Milky Way as a dry Galaxy • Physics • 2019 We construct a model for the Milky Way Galaxy composed of a stellar disc and bulge embedded in a dark-matter halo. All components are modelled as$N\$-body systems with up to 8 billion equal-massExpand
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• Physics
• The Astrophysical Journal
• 2019
The stellar populations in the inner kiloparsecs of the Milky Way (MW) show complex kinematical and chemical structures. The origin and evolution of these structures is still under debate. Here weExpand
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• 2021
Galaxy flybys are as common as mergers in low redshift universe and are important for galaxy evolution as they involve the exchange of significant amounts of mass and energy. In this study weExpand
Building the peanut: simulations and observations of peanut-shaped structures and ansae in face-on disk galaxies
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(X/peanut)-shaped features observed in a significant fraction of disk galaxies are thought to have formed from vertically buckled bars. Despite being three dimensional structures, they areExpand

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