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Related papers: The Galactic Bar

200 papers

This paper presents an equilibrium model of a Milky Way-like spiral galaxy that supports open, mostly 2- and 3-arm spiral patterns but does not form a bar. It is suggested as a more realistic alternative model to that employed by the Agora…

Astrophysics of Galaxies · Physics 2025-11-05 J A Sellwood

We make use of recent estimates for the parameters of the Milky Way's halo globular clusters and study the influence of the galactic bar on the dynamics of these clusters by computing their orbits. We use both an axisymmetric and…

Astrophysics of Galaxies · Physics 2023-03-13 Roman Tkachenko , Vladimir Korchagin , Anna Jmailova , Giovanni Carraro , Boris Jmailov

Self-consistent hybrid N-body and SPH simulations are used to give a new and coherent interpretation of the main features standing out from the HI and CO longitude-velocity observations within the Galactic bar. In particular, the traces of…

Astrophysics · Physics 2009-10-31 R. Fux

This paper describes a framework for studying galaxy morphology, particularly bar strength, in a quantitative manner, and presents applications of this approach that reveal observational evidence for secular evolution in bar morphology. The…

Astrophysics · Physics 2007-05-23 M. R. Merrifield

Secular evolution gradually shapes galaxies by internal processes, in contrast to early cosmological evolution which is more rapid. An important driver of secular evolution is the flow of gas from the disk into the central regions, often…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 Johan H. Knapen

Like many galaxies of its size, the Milky Way is a disk with prominent spiral arms rooted in a central bar, although our knowledge of its structure and origin is incomplete. Traditional attempts to understand the Galaxy's morphology assume…

Astrophysics of Galaxies · Physics 2011-09-15 Chris W. Purcell , James S. Bullock , Erik Tollerud , Miguel Rocha , Sukanya Chakrabarti

The nature of our Milky Way Galaxy is reexamined from an eclectic point of view. Evidence for a central bar, for example, is not reflected in the distribution of RR Lyrae variables in the central bulge [4,5], and it is not clear if either a…

Astrophysics of Galaxies · Physics 2015-06-17 David G. Turner

Galactic bars can affect the evolution of galaxies by redistributing gas in galaxies, possibly contributing to the cessation of star formation. Recent works point to 'bar quenching' playing an important role in massive disk galaxies like…

Astrophysics of Galaxies · Physics 2020-01-22 Lucy Newnham , Kelley Hess , Karen Masters , Sandor Kruk , Samanta Penny , Tim Lingard , Rebecca Smethurst

Non-uniqueness of deprojecting the integrated light distribution of a nearby or faraway triaxial body is reviewed in the context of deriving the volume density of the Galactic bar from the COBE/DIRBE maps of the Galactic plane. The exact…

Astrophysics · Physics 2009-09-25 HongSheng Zhao

Gas morphology and kinematics in the Milky Way contain key information for understanding the formation and evolution of our Galaxy. We present a high resolution hydrodynamical simulation based on a realistic barred Milky Way potential…

Astrophysics of Galaxies · Physics 2022-02-02 Zhi Li , Juntai Shen , Ortwin Gerhard , Jonathan P. Clarke

We re-analyse photometric near-infrared data in order to investigate why it is so hard to get a consensus for the shape and density law of the bulge, as seen from the literature. To solve the problem we use the Besancon Galaxy Model to…

Astrophysics of Galaxies · Physics 2015-06-03 Annie C. Robin , Douglas J. Marshall , Mathias Schultheis , Celine Reyle

Bars are ubiquitous morphological features in the observed distribution of galaxies. There are similarly many methods for classifying these features and, without a strict theoretical definition or common standard practice, this is often…

As the nearest large spiral galaxy, M31 provides a unique opportunity to learn about the structure and evolutionary history of this galaxy type in great detail. Among the many observing programs aimed at M31 are microlensing studies, which…

Astrophysics of Galaxies · Physics 2018-03-21 Michael Opitsch , Maximilian H. Fabricius , Roberto P. Saglia , Ralf Bender , Matias Blaña , Ortwin Gerhard

We use a sample of 938 red clump giant stars located in the direction of the galactic long bar to study the chemistry of Milky Way bar stars. Kinematically separating stars on bar orbits from stars with inner disc orbits, we find that stars…

Astrophysics of Galaxies · Physics 2019-12-18 C. Wegg , A. Rojas-Arriagada , M. Schultheis , O. Gerhard

Almost 80 years have passed since Trumpler's analysis of the Galactic open cluster system laid one of the main foundations for understanding the nature and structure of the Milky Way. Since then, the open cluster system has been recognised…

Astrophysics of Galaxies · Physics 2015-05-14 Andre Moitinho

Many barred galaxies, possibly including the Milky Way, have cusps in the centres. There is a widespread belief, however, that usual bar instability taking place in bulgeless galaxy models is impossible for the cuspy models, because of the…

Astrophysics of Galaxies · Physics 2017-02-07 E. V. Polyachenko , P. Berczik , A. Just

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

We present a dynamical study of the effect of the bar and spiral arms on the simulated orbits of open clusters in the Galaxy. Specifically, this work is devoted to the puzzling presence of high-altitude open clusters in the Galaxy. For this…

Astrophysics of Galaxies · Physics 2016-01-18 L. A. Martinez-Medina , B. Pichardo , E. Moreno , A. Peimbert , H. Velazquez

There is evidence that the distribution of suspected cosmic ray sources are associated with the spiral arm structure of galaxies. It is yet not clearly understood what effect such a cosmic ray source distribution has on the particle…

High Energy Astrophysical Phenomena · Physics 2015-06-23 M. Werner , R. Kissmann , A. W. Strong , O. Reimer

In the absence of an interaction, central bars might be the most effective mechanism for radial motions of gas in barred spiral galaxies, which represent two-thirds of disc galaxies. The dynamical effects induced by bars in the first few…

Astrophysics of Galaxies · Physics 2013-12-20 O. Cavichia , M. Mollá , R. D. D. Costa , W. J. Maciel