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Related papers: The 3D structure of the Galactic bulge

200 papers

The majority of massive disk galaxies, including our own, have stellar bars with vertically thick inner regions -- so-called "boxy/peanut-shaped" (B/P) bulges. The most commonly suggested mechanism for the formation of B/P bulges is a…

Astrophysics of Galaxies · Physics 2016-07-20 Peter Erwin , Victor P. Debattista

Recent data from the VVV survey have strengthened evidence for a structural change in the Galactic bulge inwards of |l|<=4 deg. Here we show with an N-body barred galaxy simulation that a boxy bulge formed through the bar and buckling…

Astrophysics of Galaxies · Physics 2015-06-03 Ortwin Gerhard , Inma Martinez-Valpuesta

The Milky Way has a barred bulge. This article summarizes the current understanding of the main structural parameters and pattern speed of the bar, and compares predicted values for the microlensing optical depth with the bulge microlensing…

Astrophysics · Physics 2008-11-26 Ortwin Gerhard

An overview is given of the results obtained about Galactic Structure studies towards the Galactic Centre from star counts. The results indicate the presence of an old, metal-rich population (Z=0.005-0.08; t=13-15 Gyr), presumably the old…

Astrophysics · Physics 2007-05-23 Y. K. Ng

I discuss several aspects of secular evolution linked to bars and to boxy/peanut bulges, based on a very large number of high resolution, fully self-consistent $N$-body simulations. When the bar forms, it is as thin as the disc. Its…

Astrophysics · Physics 2007-05-23 E. Athanassoula

Double-barred galaxies are common in the local Universe, with approximately one third of barred spirals hosting an smaller, inner bar. Nested bars have been proposed as a mechanism for transporting gas to the very central regions of the…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 A. de Lorenzo-Cáceres , A. Vazdekis , J. A. L. Aguerri , E. M. Corsini , Victor P. Debattista

Studies of the red clump giant population in the inner Milky Way suggest the Galactic bulge/bar has a boxy/peanut/X-shaped structure as predicted by its formation via a disc buckling instability. We used a non-parametric method of…

Astrophysics of Galaxies · Physics 2023-08-10 Dylan Paterson , Brenna Coleman , Chris Gordon

Near infrared images from the COBE satellite presented the first clear evidence that our Milky Way galaxy contains a boxy shaped bulge. Recent years have witnessed a gradual paradigm shift in the formation and evolution of the Galactic…

Astrophysics of Galaxies · Physics 2015-12-09 Juntai Shen , Zhao-Yu Li

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…

Astrophysics of Galaxies · Physics 2017-08-30 Bogdan C. Ciambur , Alister W. Graham , Joss Bland-Hawthorn

Our knowledge on the central components of disk galaxies has grown substantially in the past few decades, particularly so in the last. This frantic activity and the complexity of the subject promote confusion in the community. In these…

Cosmology and Nongalactic Astrophysics · Physics 2012-08-14 Dimitri A. Gadotti

Numerous studies of integrated starlight, stellar counts, and kinematics have confirmed that the Milky Way is a barred galaxy. However, far fewer studies have investigated the bar's stellar population properties, which carry valuable…

Inner regions of barred disk galaxies often include asymmetrical, small-scale central features, some of which are best described as secondary bars. Because orbital timescales in the galaxy center are short, secondary bars are likely to be…

Astrophysics · Physics 2007-05-23 Witold Maciejewski , Linda S. Sparke

We present the metallicity results from the ARGOS spectroscopic survey of the Galactic bulge. Our aim is to understand the formation of the Galactic bulge: did it form via mergers, as expected from Lambda CDM theory, or from disk…

Astrophysics of Galaxies · Physics 2015-06-12 M. Ness , K. Freeman , E. Athanassoula , E. Wylie de Boer , J. Bland Hawthorn , M. Asplund , G. F. Lewis , D. Yong , R. R. Lane , L. L. Kiss

Evidence from a variety of sources points towards the existence of a bar in the central few kpc of the Galaxy. The measurements roughly agree on the direction of the bar major axis, but other parameters (axis ratio, size, pattern speed) are…

Astrophysics · Physics 2008-02-03 Konrad Kuijken

This paper is the second part of Garzon et al. (1997: ApJ 491, L31) in which we presented an outline of the analysis of 60 spectra from a follow-up program to the Two Micron Galactic Survey (TMGS) project in the l=27 deg., b=0 deg. area. In…

The Milky Way is a barred galaxy whose central bulge has a box/peanut shape and consists of multiple stellar populations with different orbit distributions. This review describes dynamical and chemo-dynamical equilibrium models for the…

Astrophysics of Galaxies · Physics 2018-08-22 Ortwin Gerhard

It has been suggested that the boxy and peanut-shaped bulges found in some edge-on galaxies are galactic bars viewed from the side. We investigate this hypothesis by presenting emission-line spectra for a sample of 10 edge-on galaxies that…

Astrophysics · Physics 2016-08-30 Michael R. Merrifield , Konrad Kuijken

The bulge is a region of the Galaxy of tremendous interest for understanding galaxy formation. However measuring photometry and kinematics in it raises several inherent issues, such as severe crowding and high extinction in the visible.…

Astrophysics · Physics 2008-12-22 C. Reyle , D. J. Marshall , M. Schultheis , A. C. Robin

A vertical X-shaped structure was recently reported in the Galactic bulge. Here we present evidence of a similar X-shaped structure in the Shen et al. (2010) bar/boxy bulge model that simultaneously matches the stellar kinematics…

Astrophysics of Galaxies · Physics 2015-06-05 Zhao-Yu Li , Juntai Shen

The color-magnitude diagrams of $\sim 7 \times 10^5$ stars obtained for 12 fields across the Galactic bulge with the OGLE project reveal a well-defined population of bulge red clump giants. We find that the distributions of the apparent…

Astrophysics · Physics 2009-10-28 K. Z. Stanek , A. Udalski , M. Szymanski , J. Kaluzny , M. Kubiak , M. Mateo , W. Krzeminski