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Related papers: Bars do drive spiral density waves

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We have modelled 38 barred galaxies by using near-IR and optical data from the Ohio State University Bright Spiral Galaxy Survey. We constructed the gravitational potentials of the galaxies from $H$-band photometry, assuming constant…

Astrophysics · Physics 2009-11-13 P. Rautiainen , H. Salo , E. Laurikainen

High resolution N-body simulations using different codes and initial condition techniques reveal two different behaviours for the rotation frequency of transient spiral arms like structures. Whereas unbarred disks present spiral arms nearly…

We present the first study of bars in the local Universe, based on the Sloan Digitized Sky Survey (SDSS). The large sample of ~5000 local galaxies provides the largest study to date of local bars and minimizes the effect of cosmic variance.…

Astrophysics · Physics 2009-11-11 Fabio D. Barazza , Shardha Jogee , Irina Marinova

In the density wave theory of spiral structure, the grand-design two-armed spiral pattern is taken to rotate rigidly in a galactic disc with a constant, definite pattern speed. The observational measurement of the pattern speed of the…

Astrophysics of Galaxies · Physics 2016-06-01 Soumavo Ghosh , Chanda J Jog

With the prime aim of better probing and understanding the intimate link between star formation activity and the presence of bars, a representative sample of 32 non-interacting late-type galaxies with well-determined bar properties has been…

Astrophysics · Physics 2007-05-23 L. Martinet , D. Friedli

Observations and simulations of barred spiral galaxies have shown that, in general, the spiral arms rotate at a different pattern speed to that of the bar. The main conclusion from the bibliography is that the bar rotates faster than the…

Astrophysics of Galaxies · Physics 2022-11-09 M. Harsoula , C. Efthymiopoulos , G. Contopoulos , A. C. Tzemos

We examine the bar instability in galactic models with an exponential disk and a cuspy dark matter (DM) halo with a Navarro-Frenk-White (NFW) cosmological density profile. We construct equilibrium models from a 3-integral composite…

Astrophysics · Physics 2011-02-11 John Dubinski , Ingo Berentzen , Isaac Shlosman

We show by numerical simulations that a purely stellar dynamical model composed of an exponential disc, a cuspy bulge, and an NFW halo with parameters relevant to the Milky Way Galaxy is subject to bar formation. Taking into account the…

Astrophysics of Galaxies · Physics 2016-08-17 Evgeny Polyachenko , Peter Berczik , Andreas Just

Properties of bars and bulges in the Hubble sequence are discussed, based on the analysis of 216 disk galaxies (S0s and spirals from NIRS0S and OSUBGS surveys, respectively). For that purpose we have collected together, and completed when…

Astrophysics · Physics 2009-11-13 E. Laurikainen , H. Salo , R. Buta , J. H. Knapen

Using analytic stability criteria, we demonstrate that, due to their low surface mass density and large dark matter content, LSB disks are quite stable against the growth of global nonaxisymmetric modes such as bars. However, depending on…

Astrophysics · Physics 2007-05-23 Chris Mihos , Stacy McGaugh , Erwin de Blok

We investigate the properties of massive, dense clouds formed in a barred galaxy and their possible relation to star formation, performing a two-dimensional hydrodynamical simulation with the gravitational potential obtained from the 2Mass…

Astrophysics of Galaxies · Physics 2015-06-05 M. Nimori , A. Habe , K. Sorai , Y. Watanabe , A. Hirota , D. Namekata

Stellar bars are the most common non-axisymmetric structures in galaxies and their impact on the evolution of disc galaxies at all cosmological times can be significant. Classical theory predicts that stellar discs are stabilized against…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-15 Kanak Saha , Thorsten Naab

Bars and spiral arms have played an important role as constraints on the dynamics and on the distribution of dark matter in the optical parts of disk galaxies. Dynamics linked to the dissipative nature of gas, and its transformation into…

Astrophysics · Physics 2016-01-27 Daniel Pfenniger , Yves Revaz

We have undertaken a survey of H alpha emission in a substantially complete sample of CGCG galaxies of types Sa and later within 1.5 Abell radii of the centres of 8 low-redshift Abell clusters. Some 320 galaxies were surveyed, of which 116…

Astrophysics · Physics 2009-10-31 C. Moss , M. Whittle

More than 50 per cent of present-day massive disc galaxies show a rotating stellar bar. Their formation and dynamics have been widely studied both numerically and observationally. Although numerical simulations in the $\Lambda$CDM…

Astrophysics of Galaxies · Physics 2022-01-17 Ornela F. Marioni , Mario G. Abadi , Stefan Gottlöber , Gustavo Yepes

Barred structures are widespread in a considerable fraction of galactic discs, spanning diverse environments and galaxy luminosities. The environment likely exerts a significant influence on bar formation. It is plausible that the…

Astrophysics of Galaxies · Physics 2023-09-22 J. Alfonso L. Aguerri , Virginia Cuomo , Azahara Rojas-Roncero , Lorenzo Morelli

(Abridge) Bars are very common in the centre of the disc galaxies, and they drive the evolution of their structure. A volume-limited sample of 2106 disc galaxies extracted from the Sloan Digital Sky Survey Data Release 5 was studied to…

Astrophysics of Galaxies · Physics 2009-11-13 J. A. L. Aguerri , J. Mendez-Abreu , E. M. Corsini

Bar structures can form internally due to the instability of their host galaxies or externally due to perturbations from other galaxies. We systematically quantify the growth timescales ($\tau_\mathrm{bar}$) of bars formed through these two…

Astrophysics of Galaxies · Physics 2025-07-01 Yirui Zheng , Juntai Shen , Xufen Wu , Bin-Hui Chen

An analysis of the NICMOS Deep Field shows that there is no evidence of a decline in the bar fraction beyond z~0.7, as previously claimed; both bandshifting and spatial resolution must be taken into account when evaluating the evolution of…

We investigate the bar fraction in galaxy pairs from the SDSS to assess how galaxy interactions affect bar structures. Compared to isolated galaxies, close pairs exhibit a significantly reduced bar fraction at projected separations within…

Astrophysics of Galaxies · Physics 2026-02-17 Linlin Li , Shuai Feng , Shiyin Shen , Qi'an Deng , Ying Zu , Wenyuan Cui
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