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Related papers: Another bar in the Bulge

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We report idealized simulations that mimic the growth of galaxy disks embedded in responsive halos and bulges. The disks manifested an almost overwhelming tendency to form strong bars that we found very difficult to prevent. We found that…

Astrophysics of Galaxies · Physics 2017-10-11 Joel C. Berrier , J. A. Sellwood

The strong time-dependence of the dynamics of galactic bars yields a complex and rapidly evolving distribution of dense gas and star forming regions. Although bars mainly host regions void of any star formation activity, their extremities…

Astrophysics of Galaxies · Physics 2015-10-28 F. Renaud , F. Bournaud , E. Emsellem , O. Agertz , E. Athanassoula , F. Combes , B. Elmegreen , K. Kraljic , F. Motte , R. Teyssier

We have obtained long-slit spectroscopy for a sample of 20 early-type barred galaxies to study the influence of bars in the building of galaxy bulges. Line strength indices were measured and used to derive age and metallicity gradients in…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 Isabel Perez , Patricia Sanchez-Blazquez

We introduce a new approach to classify barred galaxies that utilizes the transverse-to-radial force ratio map (ratio map, hereafter) in a different manner from previous studies. When we display the ratio map in polar coordinates, barred…

Astrophysics of Galaxies · Physics 2020-08-26 Yun Hee Lee , Myeong-Gu Park , Hong Bae Ann , Taehyun Kim , Woo-Young Seo

Bars are common galactic structures in the local universe that play an important role in the secular evolution of galaxies, including the Milky Way. In particular, the velocity distribution of individual stars in our galaxy is useful to…

Elongated bar-like features are ubiquitous in galaxies, occurring at the centers of approximately two-thirds of spiral disks in the nearby Universe. Due to gravitational interactions between the bar and the other components of galaxies, it…

The Galactic Bulge, as the center of the Galaxy, is the closest laboratory for studying galaxy formation and evolution. However, its study faces significant challenges due to heavy dust extinction. This paper is devoted to deriving the…

Astrophysics of Galaxies · Physics 2026-03-10 Jialu Nie , Martín López-Corredoira , Chao Liu , Hai-feng Wang , Iulia Simion

While bars are common in disk galaxies, their formation conditions are not well understood. We use $N$-body simulations to study bar formation and evolution in isolated galaxies consisting of a stellar disk, a classical bulge, and a dark…

Astrophysics of Galaxies · Physics 2023-01-25 Dajeong Jang , Woong-Tae Kim

It has been known for some time that the Milky Way is a barred disk galaxy. More recently several studies inferred from starcount observations that the Galaxy must contain a separate, new, flat long bar component, twisted relative to the…

Astrophysics of Galaxies · Physics 2015-05-28 Inma Martinez-Valpuesta , Ortwin Gerhard

Simulations have shown that bars are subject to a vertical buckling instability that transforms thin bars into boxy or peanut-shaped structures, but the physical conditions necessary for buckling to occur are not fully understood. We use…

Astrophysics of Galaxies · Physics 2017-08-23 Zhao-Yu Li , Luis C. Ho , Aaron J. Barth

It has been suggested that the peanut-shaped bulges seen in some edge-on disk galaxies are due to the presence of a central bar. Although bars cannot be detected photometrically in edge-on galaxies, we show that barred potentials produce a…

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

We present an analysis of the structure, kinematics, and chemo-dynamical properties of the Milky Way bulge using RR Lyrae stars from OGLE, and giant stars from APOGEE and Gaia that have distances placing them in the inner Galaxy. Firstly,…

Astrophysics of Galaxies · Physics 2025-03-25 Xiao Han , Hai-Feng Wang , Giovanni Carraro , Martín López-Corredoira , Yuan-Sen Ting , Yang-Ping Luo , Guan-Yu Wang

Using the method of integral-field (3D) spectroscopy, we have investigated the kinematics and distribution of the gas and stars at the center of the early-type spiral galaxy with a medium scale bar NGC 7177 as well as the change in the mean…

Cosmology and Nongalactic Astrophysics · Physics 2010-04-28 Olga K. Sil'chenko , Aleksandrina A. Smirnova

Stellar bars are a common morphological feature of spiral galaxies. While it is known that they can form in isolation, or be induced tidally, few studies have explored the production of stellar bars in galaxy merging. We look to investigate…

Astrophysics of Galaxies · Physics 2020-09-16 Mitchell Cavanagh , Kenji Bekki

We present the results of two-component (disc+bar) and three-component (disc+bar+bulge) multiwavelength 2D photometric decompositions of barred galaxies in five SDSS bands ($ugriz$). This sample of $\sim$3,500 nearby ($z<0.06$) galaxies…

Although more than two-thirds of star-forming disk galaxies in the local universe are barred, some galaxies remain un-barred, occupying the upper half of the Hubble tuning fork diagram. Numerical simulations almost always produce bars…

Astrophysics of Galaxies · Physics 2018-05-16 Kanak Saha , Bruce Elmegreen

Although at least one quarter of early-type barred galaxies host secondary stellar bars embedded in their large-scale primary counterparts, the dynamics of such double barred galaxies are still not well understood. Recently we reported…

Astrophysics · Physics 2008-12-18 Juntai Shen , Victor P. Debattista

Boxy, peanut- or X-shaped "bulges" are observed in a large fraction of barred galaxies viewed in, or close to, edge-on projection, as well as in the Milky Way. They are the product of dynamical instabilities occurring in stellar bars, which…

Astrophysics of Galaxies · Physics 2020-12-23 Bogdan C. Ciambur , Francesca Fragkoudi , Sergey Khoperskov , Paola Di Matteo , Françoise Combes

I present results from the modeling of stellar bars in nearly 300 barred galaxies in the local universe through parametric multi-component multi-band image fitting. The surface brightness radial profile of bars is described using a Sersic…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 Dimitri A. Gadotti

Prompted by work on the buckling instability in barred spiral galaxies, much effort has been devoted lately to the study of boxy/peanut-shaped (B/PS) bulges. Here, we present new bar diagnostics for edge-on spiral galaxies based on periodic…

Astrophysics · Physics 2007-05-23 M. Bureau , K. C. Freeman , E. Athanassoula