相关论文: Rings and spirals in barred galaxies. II. Ring and…

We propose a theory to explain the formation of both spirals and rings in barred galaxies using a common dynamical framework. It is based on the orbital motion driven by the unstable equilibrium points of the rotating bar potential. Thus,…

In this and in a previous paper (Romero-Gomez et al. 2006) we propose a theory to explain the formation of both spirals and rings in barred galaxies using a common dynamical framework. It is based on the orbital motion driven by the…

In this paper we present building blocks which can explain the formation and properties both of spirals and of inner and outer rings in barred galaxies. We first briefly summarise the main results of the full theoretical description we have…

In a series of papers, we propose a theory to explain the formation and properties of rings and spirals in barred galaxies. The building blocks of these structures are orbits guided by the manifolds emanating from the unstable Lagrangian…

Two-armed, grand design spirals and inner and outer rings in barred galaxies can be due to orbits guided by the manifolds emanating from the vicinity of the L1 and L2 Lagrangian points, located at the ends of the bar. We first summarise the…

We propose a new theory to explain the formation of spiral arms and of all types of outer rings in barred galaxies. We have extended and applied the technique used in celestial mechanics to compute transfer orbits. Thus, our theory is based…

We propose a theory to explain the formation of spiral arms and of all types of outer rings in barred galaxies, extending and applying the technique used in celestial mechanics to compute transfer orbits. Thus, our theory is based on the…

Rings and spiral arms are distinctive features of many galaxies, and their properties are closely related to the disk dynamics. They are often associated to stellar bars, but the details of this connection are far from clear. We study the…

According to one version of the recently proposed "manifold" theory that explains the origin of spirals and rings in relation to chaotic orbits, galaxies with stronger bars should have a higher spiral arms pitch angle when compared to…

In the manifold theory of spiral structure in barred galaxies, the usual assumption is that the spirals rotate with the same pattern speed as the bar. Here we generalize the manifold theory under the assumption that the spirals rotate with…

We propose a new theory for the formation of rR_1 ring structures, i.e. for ring structures with both an inner and an outer ring, the latter having the form of ``8''. We propose that these rings are formed by material from the stable and…

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…

A method which we have developed for determining corotation radii, has allowed us to map in detail the radial resonant structures of barred spiral galaxies. Here we have combined this information with new determinations of the bar strength…

We establish a dynamical mechanism to explain the origin of the asymmetry between the arms observed in some barred disk galaxies, where one of the two arms emanating from the bar ends is very well defined, while the second one displays a…

Although nuclear rings of gas and star formation are common in barred spiral galaxies, current theories of why and how they form do not provide the level of detail needed to quantify the effect that these rings can have on the fueling of…

We argue that inner rings in barred spiral galaxies are associated with specific 2D and 3D families of periodic orbits located just beyond the end of the bar. These are families located between the inner radial ultraharmonic 4:1 resonance…

The causes of spiral structure in galaxies remain uncertain. Leaving aside the grand bisymmetric spirals with their own well-known complications, here we consider the possibility that multi-armed spiral features originate from density…

This paper, the first of two, introduces an observational study of spiral structure in galaxies chosen from the SINGS survey. Near infrared (NIR) and optical data are used to produce mass surface density maps, and from these the morphology…

We consider a scenario of formation of the spiral structure in barred galaxies. This scenario includes the new non-resonant mechanism of elongation of spirals, due to the characteristic behaviour of the gravitational potential beyond the…

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…