English
Related papers

Related papers: Lopsided galactic bars

200 papers

We investigate the dynamical effects of an interaction between an initially barred galaxy and a small spherical companion using an N-body/SPH algorithm. In the models described here the small companion passes through the disc of the larger…

Astrophysics · Physics 2009-11-07 I. Berentzen , E. Athanassoula , C. H. Heller , K. J. Fricke

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

There is no doubt that the Milky Way is a barred galaxy; however, factors that establish its prominent morphology remain largely elusive and poorly comprehended. In this work, we attempt to constrain the history of the MW by tracing the…

Astrophysics of Galaxies · Physics 2024-07-16 Sergey Khoperskov , Ivan Minchev , Matthias Steinmetz , Bridget Ratcliffe , Jakob C. Walcher , Noam Libeskind

We built three models for the gravitational field of the Galactic bar. These models are an inhomogeneous ellipsoid, an inhomogeneous prolate spheroid, and a superposition of four inhomogeneous ellipsoids. Among the three models, the…

Astrophysics · Physics 2009-11-10 Barbara Pichardo , Marco Martos , Edmundo Moreno

We address the effects of bar-driven secular evolution in discs by comparing their properties in a sample of nearly 700 unbarred and barred (42 +- 3 per cent of the population) massive disc galaxies (M* > 10^10 Msun). We make use of…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-11 Rubén Sánchez-Janssen , Dimitri A. Gadotti

The lopsidedness of galaxies is a commonly observed phenomenon, and through different studies, it has been observed that nearly 30% of galaxies show this phenomenon. In this work, we study morphological lopsidedness in both stellar and gas…

Astrophysics of Galaxies · Physics 2026-04-27 Prerana Biswas , Narendra Nath Patra , Veselina Kalinova

From this vast subject, I will pick out and review three specific topics, namely the formation and evolution of bars, the formation of bulges, and the evolution during multiple major mergers. Bars form naturally in galactic discs. Their…

Astrophysics · Physics 2009-11-13 E. Athanassoula

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

Many observed disc galaxies harbour a central bar. In the standard cosmological paradigm, galactic bars should be slowed down by dynamical friction from the dark matter halo. This friction depends on the galaxy's physical properties in a…

Double-barred galaxies account for almost one third of all barred galaxies, suggesting that secondary stellar bars, which are embedded in large-scale primary bars, are long-lived structures. However, up to now it has been hard to…

Astrophysics of Galaxies · Physics 2015-06-23 Herve Wozniak

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

Although stellar bars are prevalent in local galaxies, unbarred galaxies constitute a significant fraction, particularly at high redshifts. While some galaxies are unbarred by nature due to stability against the bar instability, several…

Astrophysics of Galaxies · Physics 2026-03-30 Yufan Zhou , Zhiyuan Li , Óscar Jiménez-Arranz , Santi Roca-Fàbrega

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…

We present a measurement of lopsidedness for the stellar disks of 60 field spiral galaxies in terms of the azimuthal m=1 Fourier amplitude, A_1, of the stellar light. We conjecture that this lopsidedness is caused by tidal interactions and…

Astrophysics · Physics 2009-10-28 Dennis Zaritsky , Hans-Walter Rix

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

Galactic bars are found in the majority of disc galaxies. They rotate nearly rigidly with an angular frequency called pattern speed. Previous idealised simulations have shown that bar pattern speed decreases with time due to dynamical…

Astrophysics of Galaxies · Physics 2024-12-11 Marcin Semczuk , Walter Dehnen , Ralph Schönrich , E. Athanassoula

We examine the properties of barred disc galaxies in a LCDM cosmological hydrodynamical simulation from the EAGLE project. Our study follows the formation of 269 discs identified at z = 0 in the stellar mass range 10.6 < log Mstr /M < 11.…

We study the clustering properties of barred galaxies using data from the Sloan Digital Sky Survey (SDSS). We compute projected redshift-space two-point cross-correlation functions w_p(r_p) for a sample of nearly 1000 galaxies for which we…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 Cheng Li , Dimitri A. Gadotti , Shude Mao , Guinevere Kauffmann

The life of disk galaxies is likely punctuated with the birth (spontaneous or induced), the aging (quick or slow), and the death (sudden or progressive) of bars. These events are responsible for various major changes of the galaxy which…

Astrophysics · Physics 2007-05-23 D. Friedli

The radial profiles of stars in disc galaxies are observed to be either purely exponential (Type-I), truncated (Type-II) or anti-truncated (Type-III) exponentials. Controlled formation simulations of isolated galaxies can reproduce all of…

Astrophysics of Galaxies · Physics 2017-10-04 Jakob Herpich , Gregory S. Stinson , Hans-Walter Rix , Marie Martig , Aaron A. Dutton