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Related papers: Asymptotic Orbits in Barred Spiral Galaxies

200 papers

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

Galactic spiral shocks are dominant morphological features and believed to be responsible for substructure formation within spiral arms in disk galaxies. They can also contribute a substantial amount of kinetic energy to the interstellar…

Astrophysics of Galaxies · Physics 2015-05-19 Chang-Goo Kim , Woong-Tae Kim , Eve C. Ostriker

Recent VLBI (Very Long Baseline Interferometer) observations determined the distances and proper motions of star-forming regions in spiral arms directly. They showed that star-forming regions and young stars have large peculiar motions, as…

Astrophysics of Galaxies · Physics 2009-11-05 Junichi Baba , Yoshiharu Asaki , Junichiro Makino , Makoto Miyoshi , Takayuki R. Saitoh , Keiichi Wada

Using a dataset of stars from a barred galaxy that provides instantaneous positions and velocities in the sky, we propose a method to identify its key structures, such as the central bar and spiral arms, and to determine the bar pattern…

Astrophysics of Galaxies · Physics 2025-06-24 P. Sánchez-Martín , J. Amorós , J. J. Masdemont

We study the phase space structure and the orbital diffusion from the vicinity of the vertical Lyapunov periodic orbits around the unstable Lagrangian points L1,2 in a 3D barred galaxy model. By perturbing the initial conditions of these…

Astrophysics of Galaxies · Physics 2022-09-28 M. Katsanikas , P. Patsis

The dynamics of a galactic disk in a non-axisymmetric (triaxial) dark halo is studied in detail using high-resolution, numerical, hydrodynamical models. A long-lived, two-armed spiral pattern is generated for a wide range of parameters. The…

Astrophysics of Galaxies · Physics 2015-06-03 A. V. Khoperskov , M. A. Eremin , S. A. Khoperskov , M. A. Butenko , A. G. Morozov

The way in which radial flows shape galaxy structure and evolution remains an open question. Internal drivers of such flows, such as bars and spiral arms, known to mediate gas flows in the local Universe, are now observable at high redshift…

The results of numerical simulations of the dynamics of galactic disks, which are submerged into nonaxisymmetric dark massive halo are discussed. Galaxy disks dynamics in the nonaxisymmetric (triaxial) dark halo were investigated in detail…

Cosmology and Nongalactic Astrophysics · Physics 2010-07-15 Alexander Khoperskov , Mikhail Eremin , Sergej Khoperskov , Marija Butenko , Sergej Khrapov

We argue that self-excited instabilities are the cause of spiral patterns in simulations of unperturbed stellar discs. In previous papers, we have found that spiral patterns were caused by a few concurrent waves, which we claimed were…

Astrophysics of Galaxies · Physics 2019-08-14 J. A. Sellwood , Ray G. Carlberg

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.…

In order to understand the physical mechanism underlying non-steady stellar spiral arms in disk galaxies we performed a series of N-body simulations with 1.2 and 8 million particles. The initial conditions were chosen to follow…

Astrophysics of Galaxies · Physics 2013-10-18 Diego Valencia-Enriquez , Ivanio Puerari

Strong galactic bars produced in simulations tend to undergo a period of buckling instability that weakens and thickens them and forms a boxy/peanut structure in their central parts. This theoretical prediction has been confirmed by…

Astrophysics of Galaxies · Physics 2019-04-03 Ewa L. Lokas

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 run N-body smoothed particle hydrodynamics (SPH) simulations of a Milky Way sized galaxy. The code takes into account hydrodynamics, self-gravity, star formation, supernova and stellar wind feedback, radiative cooling and metal…

Astrophysics of Galaxies · Physics 2015-06-04 Robert J. J. Grand , Daisuke Kawata , Mark Cropper

Spiral patterns in some disc galaxies have two arms in the centre, and three or more arms on the periphery. The same result is also obtained in numerical simulations of stellar and gaseous discs. We argue that such patterns may occur due to…

Astrophysics of Galaxies · Physics 2018-01-10 Lubov Spiegel , Evgeny Polyachenko

Spiral waves in active media react to small perturbations as particle-like objects. Here we apply the asymptotic theory to the interaction of spiral waves with a localized inhomogeneity, which leads to a novel prediction: drift of the…

Pattern Formation and Solitons · Physics 2010-01-25 V. N. Biktashev , D. Barkley , I. V. Biktasheva

We have discovered long-lived waves in two sets of numerical models of fast (marginally bound or unbound) flyby galaxy collisions, carried out independently with two different codes. In neither simulation set are the spirals the result of a…

Cosmology and Nongalactic Astrophysics · Physics 2011-05-16 Curtis Struck , Clare L. Dobbs , Jeong-Sun Hwang

We investigate the kinematic signatures induced by spiral and bar structure in a set of simulations of Milky Way-sized spiral disc galaxies. The set includes test particle simulations that follow a quasi-stationary density wave-like…

Spiral arms are the defining features of broad morphological classes of disc galaxies, but their nature and influence on galaxy evolution is still under debate. A key diagnostic for their nature is the spiral arm pattern speed: the radial…

Instrumentation and Methods for Astrophysics · Physics 2025-12-22 Robert J. J. Grand , Martin Roth

In the inner 3kpc of M51 we find that logarithmic spirals provide good fits to the peak intensities in molecular gas observed by BIMA in the CO (J=1-0) emission line along the spiral arms. However, we measure significant asymmetries between…

Astrophysics · Physics 2009-11-10 Alaina L. Henry , A. C. Quillen , Robert Gutermuth